Resist composition and method for producing resist pattern

Abstract

To provide a resist composition from which a resist pattern having good line edge roughness can be produced.SOLUTION: The resist composition contains a salt represented by a formula (I) and does not contain a resin. [In the formula, R1 and R2 each represent a group having an acid-labile group represented by the formula (1), or the like; R3 and R4 each represent a group represented by a formula (IA), or the like; R5 and R6 each represent a halogen atom, a fluorinated alkyl group or the like; m5 and m6 represent integers of 0-5; Q1 and Q2 each represent a fluorine atom or a perfluoroalkyl group; L1 represents a saturated hydrocarbon group; Y1 represents a substituted / unsubstituted alicyclic hydrocarbon group; and Ra1, Ra2 and Ra3 each represent an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group or the like, or a group composed of a combination thereof.]SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resist composition and a method for producing a resist pattern.

Background Art

[0002] Patent Document 1 describes salts represented by the following formulas, respectively. TIFF2025090653000001.tif56163

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention provides a salt that forms a resist pattern with better line edge roughness (LER) than a resist pattern formed by a resist composition containing the above salt.

Means for Solving the Problems

[0005] The present invention includes the following inventions. [1] A salt represented by formula (I). TIFF2025090653000002.tif3077[In formula (I), R 1 and R 2 each independently represent a group having a hydroxy group or an acid-labile group. R 3 and R 4 each independently represent a hydrogen atom or a group represented by formula (IA). However, at least one of R 3 and R 4 is a group represented by formula (IA).]​​ TIFF2025090653000003.tif3497[In formula (IA), R 5 and R 6 each independently represents a halogen atom, a C1-C6 perfluoroalkyl group, or a C1-C28 hydrocarbon group, and -CH2- contained in the hydrocarbon group may be replaced by -O -, -S-, or -CO-, or R 5 and R 6 together with the carbon atom to which they are attached may form a single bond or a C1-C6 alkanediyl bridge, and -CH2- contained in the alkanediyl bridge may be replaced by -O -, -S-, -CO-, -SO-, or -SO2-. m5 represents any integer from 0 to 5, and when m5 is 2 or more, a plurality of R may be the same or different from each other. 5 identical or different. m6 represents any integer from 0 to 5, and when m6 is 2 or more, a plurality of R may be the same or different from each other. 6 identical or different. Q and Q 1 each independently represents a fluorine atom or a C1-C6 perfluoroalkyl 2 group. L represents a C1-C24 saturated hydrocarbon group, and -CH 1 2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. Y represents an optionally substituted methyl group or an optionally substituted C3-C 1 24 alicyclic hydrocarbon group, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O -, -SO2-, or -CO-. -SO2- or -CO-. * represents a binding site.] [2]R 5 and R 6 are each independently a group having a hydroxy group or an acid-labile group as described in [1]. [3]R 1 , R 2 , R 5 and R 6 wherein the acid-labile group in R is a group represented by the formula (1) or a group represented by the formula (2) as described in [1] or [2]. a1 , R a2 and R a3 are each independently an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 1 8 carbon atoms or a combination thereof, or R and R a1 are bonded to each other a2 to form a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded . . ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a binding site.] TIFF2025090653000005.tif2277 [In formula (2), R a1’ and R a2’ are each independently a hydrogen atom or a hydrocarbon group having 1 to 1 2 carbon atoms, R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, and the -CH2- contained in the hydrocarbon group and the heterocyclic ring may be replaced by -O- or -S- . . X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.] [4]R 1 , R 2 , R 5 and R 6 in which the group having an acid-labile group is the salt according to any one of [1] to [3] represented by the formula (IB-1). TIFF2025090653000006.tif25100[In the formula (IB-1), L L 2 represents an alkanediyl group having 1 to 6 carbon atoms. R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group combining these, or R a1 and R a2 are bonded to each other to form a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded. * represents a bonding site.] * represents a bonding site.] [5]An acid generator containing the salt according to any one of [1] to [4]. [6]A resist composition containing the acid generator described in [5]. [7]The resist composition according to [6], further containing a resin containing a structural unit having an acid-labile group. composition. [8]The resist composition according to [6] or [7], wherein the structural unit having an acid-labile group contains at least one selected from the group consisting of the structural unit represented by the formula (a1-1) and the structural unit represented by the formula (a 1-2). TIFF2025090653000007.tif4597[In the formula (a1-1) and the formula (a1-2), L a1 and L a2 each independently represents -O- or *-O-(CH2)k1 represents -CO-O- where k1 represents any integer from 1 to 7, and * represents the bonding site with -CO-. R a4 and R a5 each independently represent a hydrogen atom or a methyl group. R a6 and R a7 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkene nyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these. m1 represents any integer from 0 to 14. n1 represents any integer from 0 to 10. n1’ represents any integer from 0 to 3.] A resist composition according to any one of [6] to [8], wherein the resin containing a structural unit having an acid-labile group contains a structural unit represented by formula (a2-A). TIFF2025090653000008.tif4855[In formula (a2-A), R a50 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a50 represents a single bond or * -X a51 -(A a52 -X a52 ) nb -, and * represents the bonding site with the carbon atom to which -R a50 is bonded. ​​​​​​​ A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represent -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents any integer from 0 to 4. When mb is any integer of 2 or more, the plural number of Rs a51 may be the same as or different from each other. Further containing a salt that generates an acid having a lower acidity than the acid generated from the

[10] acid generator The resist composition according to any one of [6] to [9].

[11] (1) A step of applying the resist composition according to any one of [6] to

[10] onto a substrate ; (2) A step of drying the applied composition to form a composition layer; (3) A step of exposing the composition layer; (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, A method for manufacturing a resist pattern including.

Effect of the Invention

[0006] By using the resist composition using the salt of the present invention, a resist pattern can be manufactured with good line edge roughness (LER).

Mode for Carrying Out the Invention

[0007] In this specification, the “(meth)acrylic monomer” means at least one selected from the group consisting of monomers having the structure of “CH2=CH-CO-” and monomers having the structure of “CH2=C(CH3)-CO-”. Similarly, “(meth)acrylate” and “(meth)acrylic acid” each mean at least one selected from the group consisting of “acrylate and methacrylate” respectively. "At least one selected from the group consisting of acrylic acid and methacrylic acid" and "at least one selected from the group consisting of acrylic acid and methacrylic acid "CH2=C(CH3)-CO-" or "CH2=CH-C When a structural unit having "O-" is exemplified, structural units having both groups are also included. In addition, in the groups described in this specification, straight chain structures and branched structures are For those that can have both structures, either one is acceptable. "The polymerizable C=C bond contained in the molecule becomes a -CC- group by polymerization." The term "combined group" refers to a group formed by combining two or more of the exemplified groups and appropriately changing their valences. The term "alkyl" refers to a bonded group. When stereoisomers exist, all stereoisomers are included. In this specification, the term "solid content of a resist composition" refers to the fraction of the total amount of the resist composition that is This refers to the total of all components excluding the solvent (E) described below.

[0008] <Salt represented by formula (I)> The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)"). In salt (I), the side with a negative charge is called an anion (I) and the side with a positive charge is called a cationic salt (I). It is sometimes called "On(I)". TIFF2025090653000009.tif2872[In formula (I), R 1 and R 2 each independently represents a group having a hydroxy group or an acid labile group. R 3 and R 4 each independently represents a hydrogen atom or a group represented by formula (IA), , R 3 and R 4 At least one of the groups is a group represented by formula (IA). TIFF2025090653000010.tif3492[In formula (IA), R 5 and R 6 each independently represents a halogen atom, a C1-C6 perfluoroalkyl group or a C1-C28 hydrocarbon group, and -CH2- contained in the hydrocarbon group may be replaced by -O -, -S- or -CO-, or R 5 and R 6 together with the carbon atom to which they are attached may form a single bond or a C1-C6 alkanediyl bridge, and -CH2- contained in the alkanediyl bridge may be replaced by -O- -, -S-, -CO-, -SO- or -SO2-. m5 represents any integer from 0 to 5, and when m5 is 2 or more, a plurality of R may be the same as or different from each other. 5 When m5 is 2 or more, a plurality of R may be the same as or different from each other. m6 represents any integer from 0 to 5, and when m6 is 2 or more, a plurality of R 6 may be the same as or different from each other. When m6 is 2 or more, a plurality of R Q 1 and Q 2 each independently represents a fluorine atom or a C1-C6 perfluoroalkyl group. L 1 represents a C1-C24 saturated hydrocarbon group, -CH 2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. Y 1 represents an optionally substituted methyl group or an optionally substituted C3- to C24 alicyclic hydrocarbon group, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -SO2- or -CO-. * represents a bonding site.]

[0009] R 1 and R 2 In the group having an acid-labile group, the acid-labile group has a leaving group and, upon contact with an acid, the leaving group leaves to form a hydrophilic group (e.g., a hydroxy group or a carboxy group). Examples of the group having an acid-labile group include a group having a group represented by formula (1) or a group having a group represented by formula (2). TIFF2025090653000011.tif2097 [In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 1 8 carbon atoms, or a combination thereof, or R 8 carbon atoms, or a combination thereof, or R a1 and R a2 are bonded to each other to form a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. ma and na each independently represent 0 or 1, and at least one of ma and na . ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bonding site.] TIFF2025090653000012.tif2379 [In formula (2), R a1’ and R a2’ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 1 2 carbon atoms, R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and and R a3’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, and the -CH2- contained in the hydrocarbon group and the heterocyclic ring may be replaced by -O- or -S-. X represents an oxygen atom or a sulfur atom. na' represents 0 or 1. X represents an oxygen atom or a sulfur atom. na' represents 0 or 1. * represents a binding site.

[0010] R a1 , R a2 and R a3 Examples of the alkyl group in R , R a1 , R a2 and R a3 are preferably 1 to 6, more preferably 1 to 3. R a1 , R a2 and R a3 Examples of the alkenyl group in R , isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octynyl group, isooctynyl group, nonenyl group. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in R can be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following group (* represents a binding site.). R a1 , R a2 and R a3 The carbon number of the alicyclic hydrocarbon group is preferably 3 to 16. TIFF2025090653000013.tif9142R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group in R Examples of the aryl group include a phenyl group, an anthryl group, a biphenyl group, a phenanthryl group, and the like. Examples of the combined group include a group combining an alkyl group and an alicyclic hydrocarbon group (e.g., , a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornil group, cyclo hexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyleth yl group, etc., an alkylcycloalkyl group or a cycloalkylalkyl group), an aralkyl group such as a benzyl group , an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-ter t-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-di thylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as a phenylcyclohexyl group, and the like. Preferably, ma is 0 and na is 1. When R and R a1 and R a2 are bonded to each other to form a non-aromatic hydrocarbon ring, examples of -C(R a1 )(R a2 )(R a3 ) include the following rings. The non-aromatic hydrocarbon ring preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-. TIFF2025090653000014.tif30140

[0011] Examples of the hydrocarbon group in R a1’ , R a2’ and R a3’ include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combined group include R a 1 , R a2 and R a3 are the same as those listed for the groups. R a2’ and R a3’ are bonded to each other and together with the carbon atom to which they are bonded and X form a heterocyclic ring, -C(R a1’ )(R a2’ )-X-R a3’ includes the following rings. * represents the bonding site. TIFF2025090653000015.tif18130R and R a1’ and R a2’ It is preferable that at least one of them is a hydrogen atom. na’ is preferably 0.

[0012] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 are alkyl groups, ma = 0, and n a = 1. The tert-butoxycarbonyl group is preferred as the group. In formula (1), R a1 , R a2 together with the carbon atom to which they are bonded form an adamantyl group, R a3 is an alkyl group, ma = 0, and na = 1. In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1. Examples of the group (1) specifically include the following groups. * represents the bonding site. TIFF2025090653000016.tif171163 TIFF2025090653000016.tif171163

[0013] Specific examples of the group (2) include the following groups. * represents the bonding site. TIFF2025090653000017.tif81160

[0014] The group having an acid-labile group is preferably a group represented by the formula (IB-1) or a group represented by the formula (IB-2), and more preferably a group represented by the formula (IB-1). TIFF2025090653000018.tif2689 [In the formula (IB-1), L 2 represents an alkanediyl group having 1 to 6 carbon atoms. R a1 R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group combining these, or R a1 and R a2 are bonded to each other to form a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded. * represents the bonding site. ] TIFF2025090653000019.tif2897 [In the formula (IB-2), L 3 represents an alkanediyl group having 1 to 6 carbon atoms. R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R represents a hydrocarbon group having 1 to 20 carbon atoms, or R a3’ and R a2’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded and X, and a3’ the -CH2- contained in the hydrocarbon group and the heterocyclic ring may be replaced by -O- or -S-. ​ Okay. X represents an oxygen atom or a sulfur atom. * represents a bonding site.

[0015] L 2 and L 3 Examples of the C1-C6 alkanediyl group in L and L include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-di yl group, hexane-1,6-diyl group; branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane- 1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc. The carbon number of the alkanediyl group is preferably 1-4, more preferably 1-3. 2 and L 3 Examples of the C1-C6 alkanediyl group in L and L are preferably a C1-C4 alkanediyl group, more preferably a methylene group or an ethylene group. .

[0016] R 5 and R 6 Examples of the halogen atom in R and R include fluorine atom, chlorine atom, bromine atom and iodine R 5 and R 6 Examples of the C1-C6 fluoroalkyl group in R and R include trifluoromethyl group, difluoromethyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, perfluoropropyl group, 2,2,3,3, 3-pentafluoropropyl group, perfluorobutyl group, 1,1,2,2,3,3,4, 4-octafluorobutyl group, perfluoropentyl group, 2,2,3,3,4,4,5, 5,5-nonafluoropentyl group, perfluorohexyl group and the like, alkyl fluoride groups are exemplified. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 4, more preferably 1 to 3. It is. R 5 And R 6 As the hydrocarbon group having 1 to 28 carbon atoms in R, chain hydrocarbons such as alkyl groups Hydrogen groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these are exemplified. As the alkyl group, methyl group, ethyl group, propyl group, isopropyl group, butyl group, Isobutyl group, tert-butyl group, pentyl group, hexyl group, octyl group, nonyl group, etc. The alkyl groups mentioned above are exemplified. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, and even more preferably 1 to 4. There is. The alicyclic hydrocarbon group may be monocyclic, polycyclic or spiro ring, and may be saturated or unsaturated. As the alicyclic hydrocarbon group, monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclo Pentyl group, cyclohexyl group, cyclooctyl group, cyclononyl group, cyclodecyl Group, cyclododecyl group and the like, and polycyclic cycloalkyl groups such as norbornyl group and adamantyl group are exemplified. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, still more preferably 3 to 12, and further More preferably 3 to 10. As the aromatic hydrocarbon group, phenyl group, naphthyl group, biphenyl group, anthryl group, Examples thereof include aryl groups such as a phenanthryl group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and even more preferably 6 to 10. . Examples of the combined group include a group obtained by combining the above-described alkyl group and alicyclic hydrocarbon group (such as a chloralkylalkyl group), an aralkyl group (such as a benzyl group), an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, etc.), an aryl-cycloalkyl group (a phenylcyclohexyl group, etc.).

[0017] R 5 and R 6 When -CH2- contained in the hydrocarbon group in is replaced by -O-, -S- or -CO -, the total number of carbon atoms of the hydrocarbon group before replacement is taken as the total number of carbon atoms of the hydrocarbon group. Examples of the replaced group include a hydroxy group (a group in which -CH2- contained in the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), an alkoxy group (a group in which -CH2- at any position contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -CO-O-), Examples include a group replaced by -CO-O-. Examples of the alkoxy group include alkoxy groups having 1 to 12 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, he ptyloxy group, an octyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, and a dodecyloxy group. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 13 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 13 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 13 carbon atoms, such as a methylcarbonyloxy group, an ethylcarbonyloxy group, a propyl carbonyloxy group, and a butylcarbonyloxy group. 5 R 6 and R may each independently be a group having an acid-labile group. The group having an acid-labile group 1 is R 2 and the same as those exemplified for R. m5 and m6 are each independently preferably any integer from 0 to 3, more preferably any integer from 0 to 2, and still more preferably 1 or 2. . R 5 and R 6 are each independently a fluorine atom, a fluoroalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or a combination thereof. carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or a combination thereof. the alkyl group, the alicyclic hydrocarbon group, and -CH2 contained in the combined group - may be replaced by -O-, -S-, or -CO-.), and / or , R 5 and R 6 together with the carbon atom to which they are attached form a single bond or an alkanediyl bridge having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl bridge - may be replaced by -O-, -S-, -CO-, -SO-, or -SO2-.).) is preferably formed, a fluorine atom, an alkyl fluoride group having 1 to 4 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms or a combined group thereof (the -CH2- contained in the alkyl group, the alicyclic hydrocarbon group, and the combined group - may be replaced by -O-, -S-, or -CO-.), and / or, R and R together with the carbon atom to which they are attached form a single bond or an alkanediyl bridge having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl bridge may be replaced by -O-, -S-, -CO-, -SO- 5 or -SO2-.) is more preferably formed, 6 it is even more preferable that it is a group having a hydroxy group or an acid-labile group, it is still more preferable that it is a group having a hydroxy group, a group having a group represented by formula (1), or a group having a group represented by formula (2) it is even more preferably a hydroxy group or a group represented by formula (IB-1).

[0018] Also, R 5 and R 6 together with the carbon atom to which they are attached form a single bond or ​​​​​An alkandiyl bridge having 1 to 6 carbon atoms (wherein -CH2 - contained in the alkandiyl bridge may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. ) When forming, R 5 and R 6 may be bonded to any position of the benzene ring, but among them, it is preferable to be bonded to the carbon atom adjacent to the carbon atom to which the sulfur atom is bonded among the carbon atoms of the benzene ring. For example, in formula (I), R and R 5 together with R 6 form, together with the carbon atom to which they are bonded, a single bond or an alkandiyl bridge having 1 to 6 carbon atoms (wherein -CH2- contained in the alkandiyl bridge may be replaced by -O-, -S-, -C O-, -SO- or -SO2-.).) When forming, as the cation in formula ( I), a cation having a group represented by formula (IG) etc. may be mentioned . . TIFF2025090653000020.tif3477[In formula (IG), R 5 and R 6 , m5, m6, * each represent the same meaning as described above. G 1 represents a single bond, -CH2-, -O-, -S-, -CO-, -SO- or -SO2-.]

[0019] The anion contained in the group represented by formula (IA) is the anion represented by formula (I-A). . TIFF2025090653000021.tif2964[In formula (I-A), Q 1 and Q 2 each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. L 1 ​represents a saturated hydrocarbon group having 1 to 24 carbon atoms, and -CH 2- in the saturated hydrocarbon group may be replaced by -O- or -CO-, and the hydrogen atoms contained in the saturated hydrocarbon group may be replaced by fluorine atoms or hydroxy groups. Y 1 represents an optionally substituted methyl group or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -SO2- or -CO-.]

[0020] In formula (I-A), when -CH2- contained in the saturated hydrocarbon group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the saturated hydrocarbon group. Also when -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -SO2- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the alicyclic hydrocarbon group.

[0021] Q 1 and Q 2 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms for Q include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a per fluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group and the like. 1 and Q 2 are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably both are fluorine atoms.

[0022] L 1 Examples of the divalent saturated hydrocarbon group in ​Examples include an alkyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and groups formed by combining two or more of these groups. Specifically, a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4 -diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1 ,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1 ,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane- 1,15-diyl group, a hexadecane-1,16-diyl group, and a heptadecane-1,17- diyl group, etc., which are linear alkanediyl groups; an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, 2-methylpropane- 1,3-diyl group, 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc., which are branched alkanediyl groups; a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohex ane-1,4-diyl group, a cyclooctane-1,5-diyl group, etc., which are monocyclic divalent alicyclic saturated hydrocarbon groups; a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane- 1,5-diyl group, an adamantane-2,6-diyl group, etc., which are polycyclic divalent alicyclic saturated hydrocarbon groups, and the like.

[0023] L 1 The -CH2- contained in the divalent saturated hydrocarbon group represented by is replaced by -O- or -CO-. Examples of the alternative group include a group represented by any of formula (b1-1) to formula (b1-3). In the groups represented by formula (b1-1) to formula (b1-3) and the groups represented by formula (b1-4) to formula (b1-11) which are specific examples thereof, * and ** represent bonding positions, and * represents a bonding site with -Y 1 .

[0024] TIFF2025090653000022.tif26117 [In formula (b1-1), L b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, the total number of carbon atoms of L b2 and L b3 is 22 or less. In formula (b1-2), L b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, the total number of carbon atoms of L b4 and L b5 is 22 or less. In formula (b1-3), Lb6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. L b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, the total number of carbon atoms of L b6 and L b7 is 23 or less.

[0025] Examples of the divalent saturated hydrocarbon group include the same ones as the divalent saturated hydrocarbon group of L 1 . L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom. L b5 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b6 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b7 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-. ​

[0026] L 1 The -CH2- contained in the divalent saturated hydrocarbon group represented by is replaced by -O- or -CO- As the group, a group represented by the formula (b1-1) or the formula (b1-3) is preferable.

[0027] As the group represented by the formula (b1-1), groups represented by the formulas (b1-4) to (b1-8) are exemplified. respectively. TIFF2025090653000023.tif49120 [In the formula (b1-4), L b8 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. In the formula (b1-5), L b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-. L b10 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, b9 L b10 and the total carbon number of L In the formula (b1-6), L b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, b11 L b12 and the total carbon number of L In the formula (b1-7), L b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. L b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-. L b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. However, the total number of carbon atoms of L b13 to L b15 is 19 or less. In formula (b1-8), L b16 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-. L b17 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms. L b18 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. However, the total number of carbon atoms of L b16 to L b18 is 19 or less.

[0028] L b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. Lb12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0029] Examples of the group represented by the formula (b1-3) include the groups represented by the formula (b1-9) to the formula (b1-11), respectively. are as follows. In the formula (b1-9), TIFF2025090653000024.tif23140 L b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms, hydroxy groups or alkylcarbonyloxy groups. The -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and the hydrogen atoms contained in the alkylcarbonyloxy group may be substituted with hydroxy groups. The hydrogen atoms contained in the alkylcarbonyloxy group may be substituted with hydroxy groups. However, L b19 and L b20 have a total carbon number of 23 or less. In formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms, hydroxy groups, or alkylcarbonyloxy groups. The -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and the hydrogen atoms contained in the alkylcarbonyloxy group may be substituted with hydroxy groups. However, the total carbon number of L , L b21 , L b22 and L b23 is 21 or less. In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms, hydroxy groups, or alkylcarbonyloxy groups. The -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and the hydrogen atoms contained in the alkylcarbonyloxy group may be substituted with hydroxy groups. The atom may be substituted with a hydroxy group. However, L b24 、L b25 and L b26 The total number of carbon atoms is 21 or less.

[0030] In the group represented by the formula (b1-9) to the group represented by the formula (b1-11), when a hydrogen atom contained in the saturated hydrocarbon group is substituted with an alkylcarbonyloxy group, The number of carbon atoms before replacement is taken as the number of carbon atoms of the saturated hydrocarbon group. The number of carbon atoms before replacement is taken as the number of carbon atoms of the saturated hydrocarbon group.

[0031] Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, an adamantylcarbonyloxy group and the like.

[0032] Examples of the group represented by the formula (b1-4) include the following. TIFF2025090653000025.tif16153

[0033] Examples of the group represented by the formula (b1-5) include the following. TIFF2025090653000026.tif69163

[0034] Examples of the group represented by the formula (b1-6) include the following. TIFF2025090653000027.tif44148

[0035] Examples of the group represented by the formula (b1-7) include the following. TIFF2025090653000028.tif62153

[0036] Examples of the group represented by the formula (b1-8) include the following. TIFF2025090653000029.tif23150

[0037] Examples of the group represented by formula (b1-2) include the following. JPEG2025090653000030.jpg31161

[0038] Examples of the group represented by formula (b1-9) include the following. TIFF2025090653000031.tif44137

[0039] Examples of the group represented by formula (b1-10) include the following. TIFF2025090653000032.tif92165

[0040] Examples of the group represented by formula (b1-11) include the following. TIFF2025090653000033.tif84163

[0041] Y 1 Examples of the alicyclic hydrocarbon group represented by include the groups represented by formula (Y1) to formula (Y11), formula (Y36) to formula (Y38). Y 1 When -CH2- contained in the alicyclic hydrocarbon group represented by is replaced by -O-, -SO2- or -C O-, the number thereof may be one or two or more. Examples of such a group include the groups represented by formula (Y12) to formula (Y35), formula (Y39) to formula (Y43) *. * represents the bonding site with L 1 and.

[0042] TIFF2025090653000034.tif82166

[0043] Y 1 Examples of the alicyclic hydrocarbon group represented by preferably include formula (Y1) to formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39) to formula (Y43) A group represented by any of the following, more preferably a group represented by formula (Y11), formula (Y15), formula (Y1 6), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula ( Y39), formula (Y40), formula (Y42) or formula (Y43), even more preferably a formula (Y11), formula (Y15), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42) or formula (Y43 ). ) Y 1 When the alicyclic hydrocarbon group represented by is a spiro ring containing an oxygen atom such as formula (Y28) to formula (Y35), formula (Y39) to formula ( Y40), formula (Y42) or formula (Y43), etc., the alkanediyl group between the two oxygen atoms preferably has one or more fluorine atoms. Also, among the alkanediyl groups contained in the ketal structure, the methylene group adjacent to the oxygen atom is preferably not substituted with a fluorine atom.

[0044] Y 1 As substituents of the methyl group represented by, a halogen atom, a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, a glycidyloxy group, - (CH2) ja -CO-O-R b1 group or -(CH2) ja -O-CO-R b1 (wherein , R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group combining these, and -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2- or -CO-, and the hydrogen contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group ​​ The element atom may be replaced by a hydroxy group or a fluorine atom. ja represents any integer from 0 to 4.) etc. can be mentioned. Any of the integers can be mentioned. Y 1 As the substituent of the alicyclic hydrocarbon group represented by, halogen atom, hydroxy group, hydroxy group may be substituted with an alkyl group having 1 to 16 carbon atoms (the -CH2- contained in the alkyl group may be replaced by -O- or -CO-).), an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, a glycidyloxy group, -(CH2) -CO-O-R group or -(CH2) - O-CO-R ja group (wherein, R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group combining these, and the -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2- ja or -CO-, and the hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. ja represents any integer from 0 to 4.) etc. can be mentioned. As the halogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom etc. can be mentioned. b1 R b1 As the alicyclic hydrocarbon group, for example, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, norbornyl group, adamantyl group etc. can be mentioned. The alicyclic hydrocarbon group has a chain hydrocarbon group. Any of the integers can be mentioned. As the substituent of the alicyclic hydrocarbon group represented by, halogen atom, hydroxy group, hydroxy group may be substituted with an alkyl group having 1 to 16 carbon atoms (the -CH2- contained in the alkyl group may be replaced by -O- or -CO-).), an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, a glycidyloxy group, -(CH2) -CO-O-R group or -(CH2) -O-CO-R

[0045] group (wherein, R represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group combining these, and the -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2- or -CO-, and the hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. ja represents any integer from 0 to 4.) etc. can be mentioned. As the halogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom etc. can be mentioned. As the alicyclic hydrocarbon group, for example, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, norbornyl group, adamantyl group etc. can be mentioned. The alicyclic hydrocarbon group has a chain hydrocarbon group. It may also be a methylcyclohexyl group, a dimethylcyclohexyl group, or the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 3 to 10. Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples of the aromatic hydrocarbon group having a chain hydrocarbon group with 1 to 18 carbon atoms include a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group with 3 to 18 carbon atoms include a p-cyclohexylphenyl group and a p-adamantylphenyl group. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 14, more preferably 6 to 10. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkyl group substituted with a hydroxy group include hydroxyalkyl groups such as a hydroxymethyl group and a hydroxyethyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. ​​​​​​​​​​​​​Groups in which -CH2- contained in the alkyl group is replaced by -O-, -S(O)2- or -CO- etc. include alkoxy groups, alkoxycarbonyl groups, alkylcarbonyl groups, alkyl carbonyl-oxy groups or groups combining these etc. Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyl oxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group etc. The number of carbon atoms of the alkoxy group is preferably 1 to 12 and more preferably 1 to 6 and still more preferably 1 to 4. Examples of the alkoxycarbonyl group include, for example, methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group etc. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 12 and more preferably 2 to 6 and still more preferably 2 to 4. Examples of the alkylcarbonyl group include, for example, acetyl group, propionyl group and butyryl group etc. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 12 and more preferably 2 to 6 and still more preferably 2 to 4. Examples of the alkylcarbonyl-oxy group include, for example, acetyloxy group, propionyloxy group, butyryloxy group etc. The number of carbon atoms of the alkylcarbonyl-oxy group is preferably 2 to 12 and more preferably 2 to 6 and still more preferably 2 to 4. Examples of the combined group include, for example, a group combining an alkoxy group and an alkyl group, an alkoxy group and an alkoxy group, an alkoxy group and an alkylcarbonyl group, an alkoxy group and an alkylcarbonyl-oxy group etc. Examples of the group combining these include a group combining an alkoxy group and an alkyl group, an alkoxy group and an alkoxy group, an alkoxy group and an alkylcarbonyl group, an alkoxy group and an alkylcarbonyl-oxy group etc. are included. Examples of the group combining an alkoxy group and an alkyl group include a methoxymethyl group, alkoxyalkyl groups such as a methoxyethyl group, an ethoxyethyl group, and an ethoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the group combining an alkoxy group and an alkoxy group include alkoxyalkoxy groups such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, and an ethoxyethoxy group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the group combining an alkoxy group and an alkylcarbonyl group include alkoxyalkylcarbonyl groups such as a methoxyacetyl group, a methoxypropionyl group, an ethoxyacetyl group, and an ethoxypropionyl group. The number of carbon atoms in the alkoxyalkylcarbonyl group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group combining an alkoxy group and an alkylcarbonyloxy group include alkoxyalkylcarbonyloxy groups such as a methoxyacetyloxy group, a methoxypropionyloxy group, an ethoxyacetyloxy group, and an ethoxypropionyloxy group. The number of carbon atoms in the alkoxyalkylcarbonyloxy group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced with -O-, -S(O)2-, -CO-, or the like include the groups represented by formula (Y12) to formula (Y35) and formula (Y39) to formula (Y43).

[0046] Y 1 Examples thereof include the following. TIFF2025090653000035.tif160165

[0047] Y 1 is preferably an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, more preferably an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent, even more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, even more preferably an adamantyl group which may have a substituent, and -CH2- constituting the alicyclic hydrocarbon group or adamantyl group may be replaced by -CO-, -SO2- or -CO-. Specifically, Y is preferably an adamantyl group, a hydroxyadamantyl group, an oxoadamantyl group or a group represented by formula (Y42), formula (Y100) to formula (Y114).

[0048] Examples of the anion represented by formula (I-A) include anions represented by formula (I-A-1) to formula (I-A-59) (hereinafter, may be referred to as "anion (I-A-1)" etc. according to the formula number).

[0049]

[0050]

[0051]

[0049] TIFF2025090653000036.tif83149

[0050] TIFF2025090653000037.tif99161

[0051] TIFF2025090653000038.tif136165

[0052] TIFF2025090653000039.tif183157

[0053] TIFF2025090653000040.tif116165

[0054] TIFF2025090653000041.tif62128

[0055] Here, R i2 ~R i7 is, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, a chain hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. L is a single bond or an alkanediyl group having 1 to 4 carbon atoms A41 and is. Q and Q 1 and Q 2 represent the same meaning as described above. Specific examples of the anion represented by formula (I-A) include those described in JP-A-2010-204646 No. gazette.

[0056] Preferably, the anions represented by formula (I-A) include the anions represented by formula (I-a-1) to formula (I-a- 38), respectively. TIFF2025090653000042.tif90157

[0057] TIFF2025090653000043.tif142145

[0058] TIFF2025090653000044.tif83165

[0059] TIFF2025090653000045.tif155156

[0060] Among them, anions represented by any of formula (I-a-1) to formula (I-a-3) and formula (I-a-7) to formula (I-a- 19), and formula (I-a-22) to formula (I-a-38) are preferred. Preferably.

[0061] Examples of salt (I) include the following salts. TIFF2025090653000046.tif241166

[0062] TIFF2025090653000047.tif228167

[0063] TIFF2025090653000048.tif221167

[0064] TIFF2025090653000049.tif220167

[0065] TIFF2025090653000050.tif244165

[0066] TIFF2025090653000051.tif97163

[0067] <Method for producing salt (I)> Salt (I) can be produced by reacting a salt represented by formula (I-a) with a salt represented by formula (I-b) in a solvent. It can be produced by reacting. TIFF2025090653000052.tif64162[Wherein, all symbols have the same meanings as described above. R A 、R B and R C each independently represents a hydrocarbon group having 1 to 12 carbon atoms, or R A, R B and R C may combine together to form an aromatic ring. R D represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. Examples of the solvent include chloroform, monochlorobenzene, acetonitrile, water, etc. can be mentioned. The reaction temperature is usually 15°C to 80°C, and the reaction time is usually 0.5 to 24 hours.

[0068] Examples of the salt represented by the formula (I-a) include salts represented by the following, etc., which are easily available on the market or can be easily produced by known production methods. TIFF2025090653000053.tif122163

[0069] Examples of the salt represented by the formula (I-b) include salts represented by the following formula. These salts can be easily produced by the same method as described in JP-A-2011-116747 and JP-A-2016-047815 or by known production methods. TIFF2025090653000054.tif202160

[0070] <Acid generator> The acid generator of the present invention contains the salt (I). It may contain one kind of the salt (I), or it may contain two or more kinds of the salt (I). In addition to the salt (I), the acid generator of the present invention may contain an acid generator known in the resist field (hereinafter sometimes referred to as "acid generator (B)"). The acid generator (B) may be used alone or in combination of two or more kinds. The acid generator (B) may be either nonionic or ionic. The nonionic acid generator

[0071] ​Examples of the acid generator include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxy ketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), etc. Representative examples of the ionic acid generator include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of the anion of the onium salt include sulfonate anion, sulfonylimide anion, sulfonylmethide anion, etc. For the acid generator (B), compounds that generate an acid upon irradiation as described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Patent No. 3,779, 778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc. can be used. Also, compounds produced by known methods may be used. The acid generator (B) may be used in combination of two or more.

[0072] Preferably, the acid generator (B) is a fluorine-containing acid generator, more preferably a salt represented by the formula (B1) (hereinafter sometimes referred to as "acid generator (B1)"). [In the formula (B1), Q and Q each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.

[0073] TIFF2025090653000055.tif2861 Q b1 and Q b2 ​ L b1 represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, and the -CH2- in the saturated hydrocarbon group may be replaced by -O- or -CO-, and the hydrogen atom contained in the saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. Y represents a methyl group which may have a substituent or an alicyclic hydrocarbon group having 3 to 2 4 carbon atoms which may have a substituent, and the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, - S(O)2- or -CO-. Z1 + represents an organic cation.]

[0074] Q in formula (B1) b1 and Q b2 and L b1 and Y are the same as Q in formula (I-A) described above 1 and Q 2 and L 1 and Y 1 respectively, and the same ones can be mentioned. Examples of the sulfonate anion in formula (B1) include the same ones as the anion represented by formula (I-A).

[0075] Z1 + Examples of the organic cation of include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations and organic phosphonium cations and the like. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations are more preferred. Specifically, cations represented by any of formulas (b2-1) to (b2-4) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number.) and the like can be mentioned. ​

[0076] In TIFF2025090653000056.tif, in formulas (b2-1) to (b2-4), R b4 ~R b6 each independently represents a linear hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atoms contained in the linear hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and the hydrogen atoms contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 may combine with each other to form a ring together with the sulfur atom to which they are attached, and the -CH2- contained in the ring may be replaced with -O-, -S-, or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent any integer from 0 to 5. When m2 is 2 or more, the plurality of R b7 may be the same or different, and when n2 is 2 or more, the plurality of R b8 may be the same or different. R b9 and R b10 each independently represents a linear hydrocarbon group having 1 to 36 carbon atoms or a carbon number of 3 to ​​​​​​​​​​​represents a C36 alicyclic hydrocarbon group. R b9 and R b10 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO- and may also be replaced by -O-, -S- or -CO-. is good. R b11 represents a hydrogen atom, a linear hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a linear hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the linear hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyl oxy group having 1 to 12 carbon atoms. is good. R b11 and R b12 may be bonded to each other to form a ring including -CH-CO- to which they are bonded, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO- and may also be replaced by -O-, -S- or -CO-. is good. R b13 ~R b18 each independently represents a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. L b31 represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of any one of 0 to 5. q2 and r2 each independently represent an integer of any one of 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, the plurality of Rs b13 are the same or different, and when p2 is 2 or more, the plurality of R b14 are the same or different, and when q2 is 2 or more, a plurality of Rs b15 are the same or different, r2 when it is 2 or more, a plurality of Rs b16 are the same or different, and when s2 is 2 or more, a plurality of Rs b17 is the same or different, and when t2 is 2 or more, a plurality of Rs b18 are the same or different.

[0077] The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, and an alkyl group such as a 2-ethylhexyl group. In particular, the chain hydrocarbon group of R b9 ~R b12 is preferably 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. The monocyclic alicyclic hydrocarbon group includes cycloalkyl groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, etc. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups, etc. TIFF2025090653000057.tif11158 In particular, the alicyclic hydrocarbon group of R ~R b9 ~R b12 is preferably 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

[0078] Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohe xyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyl A luadamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methyl nor bornyl group, an isobornyl group, etc. may be mentioned. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less.

[0079] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group. Aromatic hydrocarbon groups having a chain hydrocarbon group (such as a tolyl group, a xy lyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.) and aromatic hydrocarbon groups having an alicyclic hydrocarbon group (such as a p-cyclohexylphenyl group and a p-adamantyl phenyl group, etc.) may be mentioned. When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group, etc. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phen ethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.

[0080] Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a penti loxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, and a decyloxy group​​​ and dodecyloxy group etc. may be mentioned. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group and the like. etc. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. etc. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, a 2-ethylhexylcarbonyloxy group and the like. group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group and a 2-ethylhexylcarbonyloxy group and the like. oxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group and a 2-ethylhexylcarbonyloxy group and the like. oxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group and a 2-ethylhexylcarbonyloxy group and the like. oxy group and a 2-ethylhexylcarbonyloxy group and the like.

[0081] R b4 and R b5 The ring formed by R and R bonding to each other together with the sulfur atom to which they are bonded may be a monocyclic, polycyclic, aromatic, non-aromatic, saturated or unsaturated ring of any kind. Examples of this ring include rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. Also, the rings containing a sulfur atom include 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings, and for example, the following rings etc. may be mentioned. * represents the bonding site. TIFF2025090653000058.tif23143

[0082] R b9 and R b10 The ring formed by R and R together may be a monocyclic, polycyclic, aromatic, non-aromatic , saturated or unsaturated ring of any kind. Examples of this ring include 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. For example, a thiolan-1-ium ring (tetrahydrothi Examples include an ofenium ring, a thian-1-ium ring, a 1,4-oxathian-4-ium ring, etc. are mentioned. R b11 and R b12 The ring formed by combining them may be a monocyclic, polycyclic, aromatic, non-aromatic , saturated or unsaturated ring. This ring may be a 3-membered ring to a 12-membered ring, preferably a 3-membered ring to a 7-membered ring. Examples include an oxocycloheptane ring, an oxocyclohexane ring , an oxonorbornane ring, an oxoadamantane ring, etc.

[0083] Among cations (b2-1) to (b2-4), preferably, it is cation (b2 -1). Examples of cation (b2-1) include the following cations, etc. TIFF2025090653000059.tif74148

[0084] TIFF2025090653000060.tif100144

[0085] Examples of cation (b2-2) include the following cations, etc. TIFF2025090653000061.tif18150

[0086] Examples of cation (b2-3) include the following cations, etc. TIFF2025090653000062.tif26122

[0087] Examples of cation (b2-4) include the following cations, etc. TIFF2025090653000063.tif82166

[0088] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be combined arbitrarily. As the acid generator (B), preferably, it is of the formula (I-a-1) to Any one of the formulas (I-a-3), (I-a-7) to (I-a-16), (I-a-18), (I-a-19), (I-a-22) to (I-a-38) and a combination with the cation (b2-1) or the cation (b2-3) are exemplified. (I-a-3), (I-a-7) to (I-a-16), (I-a-18), (I-a-19), (I-a-22) to (I-a-38) and a combination with the cation (b2-1) or the cation (b2-3) are exemplified. Any one of the formulas (I-a-3), (I-a-7) to (I-a-16), (I-a-18), (I-a-19), (I-a-22) to (I-a-38) and a combination with the cation (b2-1) or the cation (b2-3) are exemplified.

[0089] As the acid generator (B), preferably, those represented by the formulas (B1-1) to (B1-56) are exemplified. Among them, those containing an arylsulfonium cation are preferred, and those represented by the formulas (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-56) are particularly preferred. Any one of the formulas (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-56) are particularly preferred. Any one of the formulas (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-56) are particularly preferred. Any one of the formulas (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-56) are particularly preferred. TIFF2025090653000064.tif120148

[0090] JPEG2025090653000065.jpg77148

[0091] JPEG2025090653000066.jpg148148

[0092] JPEG2025090653000067.jpg67166

[0093] TIFF2025090653000068.tif59165

[0094] TIFF2025090653000069.tif92157

[0095] When containing the salt (I) and the acid generator (B) as the acid generator, the ratio of the content of the salt (I) and the acid generator (B) (mass ratio; salt (I): acid generator (B)) is usually 1:99 to 99:1, When containing the salt (I) and the acid generator (B) as the acid generator, the ratio of the content of the salt (I) and the acid generator (B) (mass ratio; salt (I): acid generator (B)) is usually 1:99 to 99:1, Yes, preferably in the range of 2:98 to 98:2, more preferably in the range of 5:95 to 95:5 , still more preferably in the range of 10:90 to 90:10, and particularly preferably in the range of 15:85 to 85: 15. In the resist composition of the present invention, when the total content of the acid generator contains the resin (A) described below , preferably it is 1 part by mass or more and 45 parts by mass or less, more preferably 1 part by mass or more and 40 parts by mass or less, still more preferably 3 parts by mass or more and 40 parts by mass or less, and even more preferably 5 parts by mass or more and 40 parts by mass or less, based on 100 parts by mass of the resin (A). Further, when not containing the resin (A) described below, preferably it is 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition.

[0096] <Resist Composition> The resist composition of the present invention contains an acid generator containing the salt (I). The resist composition of the present invention preferably contains a resin (hereinafter sometimes referred to as "resin (A)") containing a structural unit having an acid-labile group. Here, the "acid-labile group" means a group having a leaving group, and when contacted with an acid, the leaving group leaves and the structural unit is converted into a structural unit having a hydrophilic group (for example, a hydroxy group or a carboxy group). The resist composition of the present invention more preferably contains a quencher (hereinafter sometimes referred to as "quencher (C)") such as a salt that generates an acid having a lower acidity than the acid generated from the acid generator, and more preferably contains a solvent (hereinafter sometimes referred to as "solvent (E)").

[0097] <Resin (A)> The resin (A) is a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)") It has (a certain one). The resin (A) preferably further contains structural units other than the structural unit (a1). As the structural units other than the structural unit (a1), there are structural units having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)"), structural units other than the structural unit (a1) and the structural unit (s) (for example, structural units having a halogen atom described later (hereinafter sometimes referred to as "structural unit (a4)") ), structural units having a non-leaving hydrocarbon group described later (hereinafter sometimes referred to as "structural unit (a5)") and structural units derived from other monomers known in the art and the like can be mentioned. 〈Structural unit (a1)〉 The structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)").

[0098] 〈Structural unit (a1)〉 The structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid-labile group contained in the resin (A) is preferably a group represented by the formula (1) (hereinafter also referred to as group (1)) and / or a group represented by the formula (2). In the formula (1), R , R and R a1 , R a2 and R a3 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 1 8 carbon atoms or a group combining these, or R and R a1 and R a2 are bonded to each other to form a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bonding site.] * represents a bonding site.] TIFF2025090653000071.tif2172[In formula (2), R a1’ and R a2’ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 1 2 carbon atoms, R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, and the -CH2- contained in the hydrocarbon group and the heterocyclic ring may be replaced by -O- or -S- . X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.]

[0099] Examples of the alkyl group in R a1 , R a2 and R a3 include a methyl group, an ethyl group, a prop yl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, etc. Examples of the alkenyl group in R a1 , R a2 and R a3 include an ethenyl group, a propenyl group , an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octynyl group, an isooctynyl group, a nonenyl group, etc. The alicyclic hydrocarbon group in R a1 , R a2 and R a3 may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cyclo heptyl group, a cyclooctyl group, etc. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following ​​​ Examples thereof include a group (* represents a bonding site), etc. R a1 , R a2 and R a3 The number of carbon atoms of the alicyclic hydrocarbon group of is preferably 3 to 16. TIFF2025090653000072.tif11150R Examples of the aromatic hydrocarbon group for a1 , R a2 and R a3 include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group, etc. Examples of the combined group include a group combining an alkyl group and an alicyclic hydrocarbon group (for example , methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclo hexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornyleth yl group, etc., alkylcycloalkyl group or cycloalkylalkyl group), ar alkyl group such as benzyl group, aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-ter t-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-di thylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), ar yl-cycloalkyl group such as phenylcyclohexyl group, etc. are mentioned. Preferably, ma is 0 and na is 1. R a1 and R a2 When and are bonded to each other to form a non-aromatic hydrocarbon ring, -C(R a1 )(R a2 )(R a3 ) includes the following rings. The non-aromatic hydrocarbon ring preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-.​ TIFF2025090653000073.tif30138

[0100] R a1’ 、R a2’ and R a3’ Examples of the hydrocarbon group in R include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these, etc. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combined group include those similar to the groups exemplified by R a 1 、R a2 and R a3 R a2’ and R a3’ When R and R are bonded to each other to form a heterocyclic ring together with the carbon atom to which they are bonded and X, -C(R )(R a1’ )(R a2’ )-X-R a3’ includes the following rings. * represents the bonding site. TIFF2025090653000074.tif18130R a1’ and R a2’ Preferably, at least one of them is a hydrogen atom. na' is preferably 0.

[0101] Examples of group (1) include the following groups. In formula (1), R a1 、R a2 and R a3 are alkyl groups, ma = 0, and n a = 1. Examples of such a group include a tert-butoxycarbonyl group. In formula (1), R a1 、R a2 together with the carbon atom to which they are bonded form an adamantyl group, R is an alkyl group, ma = 0, and na = 1. a3 ​​​​ In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1. The group is a group. Specific examples of the group (1) include the following groups. * represents a bonding site. TIFF2025090653000075.tif171163

[0102] Specific examples of the group (2) include the following groups. * represents a bonding site. TIFF2025090653000076.tif68162

[0103] The monomer (a1) is preferably a monomer having an acid-labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid-labile group. Among the (meth)acrylic monomers having an acid-labile group, those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms are preferably included. Using a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group in the resist composition

[0104] can improve the resolution of the resist pattern. Among the structural units derived from the (meth)acrylic monomer having the group (1), the structural unit represented by formula (a1- 0) (hereinafter sometimes referred to as the structural unit (a1-0)), the structural unit represented by formula (a1 -1) (hereinafter sometimes referred to as the structural unit (a1-1)) or the structural unit represented by formula (

[0105] a1-2) (hereinafter sometimes referred to as the structural unit (a1-2)) can be mentioned. Preferably, from the group consisting of the structural unit (a1-1) and the structural unit (a1-2) 0) (hereinafter sometimes referred to as the structural unit (a1-0)), the structural unit represented by formula (a1 -1) (hereinafter sometimes referred to as the structural unit (a1-1)) or the structural unit represented by formula ( a1-2) (hereinafter sometimes referred to as the structural unit (a1-2)) can be mentioned. Preferably, from the group consisting of the structural unit (a1-1) and the structural unit (a1-2) are exemplified. Preferably, from the group consisting of the structural unit (a1-1) and the structural unit (a1-2) It is at least one selected structural unit. These may be used alone or in combination of two or more. In TIFF2025090653000077.tif43142 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 、L a1 and L a2 each independently represents -O- or * -O-(CH2) k1 -CO -O-, k1 represents an integer from 1 to 7, and * represents the bonding site with -CO- . R a01 、R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a02 、R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group formed by combining these groups. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkene nyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group formed by combining these groups. m1 represents an integer from 0 to 14. n1 represents an integer from 0 to 10. n1’ represents an integer from 0 to 3.]

[0106] R a01 、R a4 and R a5 are preferably methyl groups. L a01 、L a1 and L a2 are preferably an oxygen atom or *-O-(CH2) k01-CO- is -O- (wherein k01 is preferably any integer from 1 to 4, more preferably 1 .), and more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a7 Examples of the alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group and the combined groups thereof in R a1 ~R a3 include the same groups as those exemplified for R in formula (1). R a02 , R a03 , and R a04 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and still more preferably a methyl group. R a6 and R a7 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group or a t-butyl group. R a6 and R a7 The alkenyl group in is preferably an alkenyl group having 2 to 6 carbon atoms, more preferably an ethenyl group, a propenyl group, an isopropenyl group or a butenyl group. R a02 , R a03 , R a04 , R a6 and R a7 The number of carbon atoms of the alicyclic hydrocarbon group of is preferably 5 to 12, and more preferably 5 to 10. R a02 , R a03 , R a04 , R a6 and R a7 The number of carbon atoms of the aromatic hydrocarbon group of is preferably It is 6 to 12, more preferably 6 to 10. The group combining an alkyl group and an alicyclic hydrocarbon group preferably has a total carbon number of 18 or less when these alkyl group and alicyclic hydrocarbon groups are combined. The group combining an alkyl group and an aromatic hydrocarbon group preferably has a total carbon number of 18 or less when these alkyl group and aromatic hydrocarbon groups are combined. R a02 and R a03 are each independently preferably an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group. R a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group is. R a6 and R a7 are each independently preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, a phenyl group or a naphth yl group, still more preferably an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group or a phenyl group. m1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1' is preferably 0 or 1.

[0107] Examples of the structural unit (a1-0) include formulas (a1-0-1) to (a1-0-18) A structural unit represented by any of the following and R in the structural unit (a1-0) a01 A methyl group corresponding to is replaced by a hydrogen atom, and examples thereof include structural units represented by any of formulas (a1-0-1) to formula (a1-0 -10), formula (a1-0-13), and formula (a1-0-14). are preferred. TIFF2025090653000078.tif103168

[0108] As the structural unit (a1-1), for example, structural units derived from the monomers described in JP-A-2010-204646 can be mentioned. Among them, the structural unit represented by any of formulas (a1-1-1) to formula (a1 -1-7) and the structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced by a hydrogen atom are preferred, and the structural unit represented by any of formulas (a1-1-1) to formula ( a4 corresponding a1-1-4) is more preferred. a1-1-4) are more preferred. TIFF2025090653000079.tif38168

[0109] As the structural unit (a1-2), structural units represented by any of formulas (a1-2-1) to formula (a1-2-12) and the structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced by a hydrogen atom can be mentioned, and structural units represented by formula (a1-2-2), formula (a1-2-5), formula a5 corresponding methyl group is hydrogen (a1-2-6) and any of formulas (a1-2-10) to formula (a1-2-12) (a1-2-6) and any of formulas (a1-2-10) to formula (a1-2-12) are preferred. are preferred. TIFF2025090653000080.tif75155

[0110] When the resin (A) contains the structural unit (a1-0), the content thereof is based on all the structural units of the resin (A) is usually 5 to 60 mol%, preferably 5 to 50 mol%, more preferably 10 to 40 mol%. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is usually 10 to 95 mol% based on all the structural units of the resin (A), preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 80 mol%, and even more preferably 30 to 75 mol%.

[0111] Examples of the structural unit having the group (2) in the structural unit (a1) include a structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as "structural unit (a1-4)"). TIFF2025090653000081.tif4766[In the formula (a1-4), R a32 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a33 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a30 represents a single bond or * -X a31 -(A a32 -X a32 ) nc - and * represents the bonding site with the carbon atom to which -R a32 is bonded. A a32 represents an alkanediyl group having 1 to 6 carbon atoms. X a31 and X​​​​​​a32 Each independently represents -O-, -CO-O- or -O-CO-. nc represents 0 or 1. la represents any integer from 0 to 4. When la is any integer of 2 or more, the plural R s may be the same as or different from each other. a33 R and R a34 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, a35 R represents a hydrocarbon group having 1 to 20 carbon atoms, or R a36 and R a35 are bonded to each other to form, together with the -C-O- to which they are bonded, a divalent hydrocarbon group having 2 to 20 carbon atoms, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. a36 The alkyl groups for R and R include, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group and hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0112] R a32 and R a33 The halogen atoms for R and R include, for example, fluorine atom, chlorine atom and bromine atom. The alkyl groups having 1 to 6 carbon atoms which may have a halogen atom include trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group, etc. R a32 and R a33 include, for example, fluorine atom, chlorine atom and bromine atom. The alkyl groups having 1 to 6 carbon atoms which may have a halogen atom include trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group, etc. ​​​​​A t-butyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoro ropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pen tyl group, a hexyl group, a perfluorohexyl group and the like can be mentioned. R a32 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pent yloxy group and a hexyloxy group. Among them, an alkoxy group having 1 to 4 carbon atoms is preferable, a methoxy group or an ethoxy group is more preferable, and a methoxy group is even more preferable. . Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymeth yl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, te rt-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a meth oxymethyl group. Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethox ymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group , a butoxymethoxy group, a sec-butoxymethoxy group, a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group and a butyryl group. It can be. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and an acetyl group is more preferable. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group and the like. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and an acetyloxy group is more preferable. R a33 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, and a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxymethoxy group is more preferable, and a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group is even more preferable.

[0113] *-X a31 -(A a32 -X a32 ) nc As *-X-(A-X)-, *-O-, *-CO-O-, *-O-C O-, *-CO-O-A a32 -CO-O-, *-O-CO-A a32 -O-, *-O-A a32 -CO-O-, *-CO-O-A a32 -O-CO-, *-O-CO-A a32 -O-CO-, can be mentioned. Among them, *-CO-O-, *-CO-O-A a32 -CO-O- or *- O-A a32 -CO-O- is preferable. Examples of the alkanediyl group include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group , a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1, 3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group and a 2-methylbutane-1,4-diyl group, etc. may be mentioned. A a32 is preferably a methylene group or an ethylene group. A a30 is a single bond, *-CO-O- or *-CO-O-A a32 -CO-O- is preferred, and a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. la is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. R a34 , R a35 and R a36 as the hydrocarbon group in is an alkyl group, an alicyclic hydrocarbon group , an aromatic hydrocarbon group, and a group combining these may be mentioned. As the alkyl group, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, hexi l group, a heptyl group, an octyl group, etc. may be mentioned. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. The monocyclic alicyclic hydrocarbon group includes cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group etc. The polycyclic alicyclic hydrocarbon group includes a decahydronaphthyl group, an adamantyl group, a norbornyl group and the following group (* represents the bonding site.) etc. are mentioned. As the aromatic hydrocarbon group, aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, TIFF2025090653000082.tif11153 a phenanthryl group, etc. may be mentioned. As the combined group, a group combining the above-described alkyl group and alicyclic hydrocarbon group (for example, cycloalkylalkyl group), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl- 6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohe xylphenyl group, p-adamantylphenyl group, etc.), aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. are exemplified. In particular, R is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a36 a group formed by combining these. is preferably a hydrogen atom. R

[0114] R a34 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a35 The hydrocarbon group of is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms. The alkyl group and alicyclic hydrocarbon group in R a36 are preferably unsubstituted. The aromatic hydrocarbon group in R is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms. R a36 in the alkyl group and alicyclic hydrocarbon group are preferably unsubstituted. a36 In R the aromatic hydrocarbon

[0115] -OC(R a34 )(R a35 )-O-R a36 is eliminated upon contact with an acid (e.g., p-toluenesulfonic acid) to form a hydroxy group. -OC(R a34 )(R a35 )-O-R a36 is preferably bonded to the o-position or p-position of the benzene ring, more preferably to the p-position. Preferably, it is bonded to the p-position, more preferably.

[0116] Examples of the structural unit (a1-4) include structural units derived from the monomers described in JP-A-2010-204646. Preferably, the structural units represented by formula (a1-4-1) to formula (a1 -4-18) and the structural units in which the hydrogen atom corresponding to R is replaced with a methyl group are included. More preferably, the structural units represented by formula (a1-4-1) to formula (a1-4- a32 5), formula (a1-4-10), formula (a1-4-13), and formula (a1-4-14) are included. respectively. 5), formula (a1-4-10), formula (a1-4-13), formula (a1-4-14) are included. respectively. TIFF2025090653000083.tif101167

[0117] When the resin (A) contains the structural unit (a1-4), its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, based on the total of all the structural units of the resin (A). Even more preferably, it is 20 to 85 mol%, even more preferably 20 to 70 mol%, even more preferably 20 to 60 mol%, and particularly preferably 20 to 60 mol%.

[0118] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) include formula (a1 The structural unit represented by (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)") is also included. It can be mentioned. In formula (a1-5) of TIFF2025090653000084.tif4659, R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. It represents an atom. Z a1 represents a single bond or *-(CH2) h3 -CO-L 54 -, h3 is any integer from 1 to 4 represents an integer, and * represents the bonding site with L 51 It represents the bonding site with L. L 51 L 52 L 53 and L 54 each independently represents -O- or -S-. s1 represents any integer from 1 to 3. s1' represents any integer from 0 to 3.

[0119] Examples of the halogen atom include a fluorine atom and a chlorine atom, and a fluorine atom is preferred. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a fluoro methyl group and a trifluoromethyl group. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. It is preferred. L 51 is preferably an oxygen atom. L 52 and L 53 Among them, it is preferred that one is -O- and the other is -S-. s1 is preferably 1. s1' is preferably any integer from 0 to 2. Z a1is preferably a single bond or *-CH2-CO-O-.

[0120] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among them, the structural units represented by formula (a1-5-1) to formula (a1-5- 4) are preferred, and the structural unit represented by formula (a1-5-1) or formula (a1-5-2 ) is more preferred. TIFF2025090653000085.tif34132

[0121] When the resin (A) contains the structural unit (a1-5), its content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, still more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol% based on all the structural units of the resin (A). When the resin (A) contains the structural unit (a1-5), its content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, still more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol% based on all the structural units of the resin (A). % is still more preferred, and 5 to 30 mol% is even more preferred.

[0122] Examples of the structural unit (a1) also include the following structural units. TIFF2025090653000086.tif30163

[0123] When the resin (A) contains the structural units such as (a1-3-1) to (a1-3-7), its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, and even more preferably 20 to 70 mol% based on all the structural units of the resin (A). is even more preferred, 20 to 60 mol% is even more preferred, and 10 to 40 mol% is particularly preferred. is preferred.

[0124] 〈Structural unit (s)〉 The structural unit (s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer (s)"). The monomer that leads to the structural unit (s) is a publicly known acid-labile monomer in the resist field. In some cases, it is called "monomer (s)". The monomer that leads to the structural unit (s) is a publicly known acid-labile monomer in the resist field. Monomers without a stabilizing group can be used. As the structural unit(s), it is preferable to have a hydroxy group or a lactone ring. Hydro xy group and having no acid-labile group structural unit (hereinafter referred to as "structural unit (a2)") and / or having a lactone ring and having no acid-labile group structural unit (hereinafter referred to as "structural ural unit (a3)") resin having a case is used in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved.

[0125] 〈Structural unit (a2)〉 The hydroxy group of the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group. When producing a resist pattern from the resist composition of the present invention, KrF excimer laser (248 nm), electron beam or EUV (extreme ultraviolet light) or other high energy rays are used In the case of, as the structural unit (a2), a structural unit having a phenolic hydroxy group ( a2) is preferable, and it is more preferable to use the structural unit (a2-A) described later. Also, When using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), the structural unit (a2-1) or the structural unit (a2-A) described later is more preferably used. The structural unit (a2) may be contained alone or in two or more kinds .

[0126] As the structural unit having a phenolic hydroxy group in the structural unit (a2), the formula (a 2-A) represented by the structural unit (hereinafter sometimes referred to as "structural unit (a2-A)") can be mentioned . TIFF2025090653000087.tif4753 [In the formula (a2-A), R a50 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a50 represents a single bond or *-X a51 -(A a52 -X a52 ) nb -, where * represents the bonding site to the carbon atom to which -R a50 is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represent -O-, -CO-O-, or -O-CO-. nb represents 0 or 1. mb represents any integer from 0 to 4. When mb is any integer of 2 or more, multiple R s may be the same as or different from each other. a51

[0127] R a50 and R a51 Examples of the halogen atom in include a fluorine atom, a chlorine atom, and a bromine atom. R a50 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2 ,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a per ​​​​​​A rufuoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoro pentyl group, a pentyl group, a hexyl group, and a perfluorohexyl group may be mentioned. R a50 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a51 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a51 Examples of the alkoxy group in include a methoxy group, an ethoxy group, a propoxy group, an isopropyl propoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a51 Examples of the alkoxyalkyl group in include a methoxymethyl group, an ethoxyethyl group , a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxy methyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a51Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a51 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a51 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a51 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0128] *-X a51 -(A a52 -X a52 ) nb Examples of *-O-, *-CO-O-, *-O-C O-, *-CO-O-A a52 -CO-O-, *-O-CO-Aa52 -O-, *-O-A a52 -CO-O-, *-CO-O-A a52 -O-CO-, *-O-CO-A a52 -O-CO-, are exemplified. Among them, *-CO-O-, *-CO-O-A a52 -CO-O- or *- O-A a52 -CO-O- is preferred.

[0129] Examples of the alkanediyl group include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group , a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1, 3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group and a 2-methylbutane-1,4-diyl group and the like. A a52 is preferably a methylene group or an ethylene group.

[0130] A a50 is a single bond, *-CO-O- or *-CO-O-A a52 -CO-O- is preferred, and a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0131] mb is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. The hydroxy group is preferably bonded to the o-position or p-position of the benzene ring, and is more preferably bonded to the p-position.

[0132] Examples of the structural unit (a2-A) include JP-A-2010-204634 and JP-A-2012- Examples of structural units include those derived from monomers described in US Pat. No. 5,12577. The structural unit (a2-A) is represented by formulas (a2-2-1) to (a2-2-12). In the structural units represented by formulas (a2-2-1) to (a2-2-12), R in structural unit (a2-A) a50 The methyl group corresponding to The structural unit (a2-A) is a structural unit represented by the formula (a2-2-1): , a structural unit represented by formula (a2-2-3), a structural unit represented by formula (a2-2-6), Structural units represented by (a2-2-8), formulas (a2-2-10) to (a2-2-12) A structural unit represented by formula (a2-2-1), a structural unit represented by formula (a2-2-3), A structural unit represented by formula (a2-2-6), a structural unit represented by formula (a2-2-8), In the structural units represented by formulas (a2-2-10) to (a2-2-12), In the structural unit (a2-A), R a50 The methyl group corresponding to is replaced by a hydrogen atom. It is preferably a structural unit. TIFF2025090653000088.tif68165

[0133] Content of structural unit (a2-A) when structural unit (a2-A) is contained in resin (A) is preferably 5 to 80 mol %, more preferably 10 to 70 mol %, based on all structural units. % by mole, more preferably 15 to 65 mol %, and even more preferably 20 to 65 mol %. It is preferably 65 mol %, and more preferably 20 to 50 mol %. The structural unit (a2-A) can be prepared, for example, by polymerization of the structural unit (a1-4) followed by p-toluenesulfonyl chloride. It can be incorporated into the resin (A) by treating it with an acid such as benzenesulfonic acid. , after polymerization using acetoxystyrene or the like, and then treating with an alkali such as tetramethylammonium hydroxide it is possible to incorporate the structural unit (a2-A) into the resin (A).

[0134] As the structural unit having an alcoholic hydroxy group in the structural unit (a2), a structural unit represented by the formula ( a2-1) (hereinafter sometimes referred to as "structural unit (a2-1)") is exemplified. In the formula (a2-1) in TIFF2025090653000089.tif4359, L a3 represents -O- or *-O-(CH2) k2 -CO-O-, k2 represents an integer of any one of 1 to 7. * represents the bonding site with -CO-. R a14 represents a hydrogen atom or a methyl group. R a15 and R a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group. o1 represents an integer of any one of 0 to 10.

[0135] In the formula (a2-1), L a3 is preferably -O-, -O-(CH2) f1 -CO-O- wherein (the said f1 represents an integer of any one of 1 to 4), and more preferably -O-. R a14 is preferably a methyl group. R a15 is preferably a hydrogen atom. R a16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of any one of 0 to 3, more preferably 0 or 1.

[0136] Examples of the structural unit (a2-1) include those described in JP-A-2010-204646. ​Examples of the structural unit derived from the monomer thus obtained include structural units represented by Formula (a2-1-1) to Formula (a2-1-6). The structural unit represented by any of Formula (a2-1-1) to Formula (a2-1-6) is preferable, and the structural unit represented by any of Formula (a2-1-1) to Formula (a2-1-4) is more preferable, and the structural unit represented by Formula (a2-1-1) or Formula (a2-1- 3) is even more preferable. TIFF2025090653000090.tif48138

[0137] When the resin (A) contains the structural unit (a2-1), the content thereof is usually 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 2 to 20 mol%, and even more preferably 2 to 10 mol% with respect to all the structural units of the resin (A).

[0138] 〈Structural unit (a3)〉 The lactone ring of the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following Formula (a3-2)) is exemplified.

[0139] The structural unit (a3) is preferably a structural unit represented by Formula (a3-1), Formula (a3-2), Formula (a3-3), or Formula (a3-4). These may be contained alone or in combination of two or more. TIFF2025090653000091.tif51162[In Formula (a3-1), Formula (a3-2), Formula (a3-3), and Formula (a3-4), L a4 、L a5 and L​​​​​​​a6 is, independently of each other, -O- or *-O-(CH2) k3 -[[]]END]] CO-O-(where k3 represents an integer from 1 to 7). L a7 is -O-, *-O-L a8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 represents -O- respectively. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding site with the carbonyl group. R a18 , R a19 and R a20 each independently represents a hydrogen atom or a methyl group. R a24 may have a halogen atom and represents an alkyl group having 1 to 6 carbon atoms, a hydrogen atom or represents a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , R a23 and R a25 each independently represents a carboxy group, a cyano group or a aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer from 0 to 5. q1 represents an integer from 0 to 3. r1 represents an integer from 0 to 3. w1 represents an integer from 0 to 8. When p1, q1, r1 and / or w1 is 2 or more, a plurality of R a21 , R a22 , R a2 3 and / or R a25 may be the same or different.]

[0140] R a21 , R a22 , R a23 and R a25 The aliphatic hydrocarbon group in The following radicals are available: ethyl, propyl, isopropyl, butyl, sec-butyl and tert-butyl. Examples of the alkyl group include a t-butyl group. R a24 The halogen atom in the formula (I) is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. Examples of atoms include: R a24 The alkyl group in the formula (I) is a methyl group, an ethyl group, a propyl group, an isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl group, etc. Of these, preferred is an alkyl group having 1 to 4 carbon atoms, and more preferred is a methyl group. or an ethyl group. R a24 Examples of the alkyl group having a halogen atom in the formula (I) include a trifluoromethyl group, Perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluoro perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoropentyl group, perfluorohexyl group, trichloromethyl group, tribromomethyl group Examples of the alkyl group include an alkyl group, a triiodomethyl group, and a triiodomethyl group.

[0141] L a8 and L a9 The alkanediyl group in the formula (I) is a methylene group, an ethylene group, a proline group, Pan-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pe hexane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pen Examples include a tan-1,4-diyl group and a 2-methylbutane-1,4-diyl group.

[0142] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or, *-O-(CH2) k3 -CO-O- where k3 is an integer from 1 to 4, more preferably -O- and, *-O-CH2-CO-O-, and even more preferably an oxygen atom. R a18 ~R a21 are each independently preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group or a me thyl group. p1, q1 and r1 are each independently preferably an integer from 0 to 2, more preferably 0 or 1.

[0143] In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-O-L a8 -CO-O-, more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. w1 is preferably an integer from 0 to 2, more preferably 0 or 1. In particular, the formula (a3-4) is preferably the formula (a3-4)'. TIFF2025090653000092.tif3846 (in the formula, R a24 , L a7 has the same meaning as above.)

[0144] As the structural unit (a3), a monomer described in JP-A-2010-204646 can be used. , Monomers described in JP 2000-122294 A, and JP 2012-41274 A Examples of the structural unit (a3) ​​include structural units derived from the monomers described in the above publication. , formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2) , Formula (a3-3-1), Formula (a3-3-2) and Formula (a3-4-1) to Formula (a3-4-1 2), and in the structural unit, the structural unit represented by any one of the formulas (a3-1) to (a3-2) R in a3-4) a18 , R a19 , R a20 and R a24 The methyl group corresponding to water Structural units which replace atomic atoms are preferred.

[0145] TIFF2025090653000093.tif115163

[0146] When the resin (A) contains the structural unit (a3), the total content of the structural unit (a3) ​​is the total content of all structural units of the resin (A). The amount is usually 5 to 70 mol %, preferably 10 to 65 mol %, more preferably Or, it is 10 to 60 mol %. In addition, the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3) or the structural unit The content of the units (a3-4) is 5 to 60 moles per total structural units of the resin (A). % by mole, more preferably 5 to 50 mol %, and further preferably 10 to 50 mol %.

[0147] 〈Structural unit (a4)〉 Examples of the structural unit (a4) include the following structural units. TIFF2025090653000094.tif2962[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having a halogen atom with 1 to 24 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.] The saturated hydrocarbon group represented by R includes a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these, etc. R 42 The saturated hydrocarbon group represented by includes a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these, etc. Examples thereof include a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these.

[0148] Examples of the chain saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group. Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; polycyclic alicyclic saturated hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents the bonding site). Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; polycyclic alicyclic saturated hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents the bonding site). Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. TIFF2025090653000095.tif11145Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group. Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and groups such as -alkanediyl group - alicyclic saturated hydrocarbon group, - alicyclic saturated hydrocarbon group - alkyl group, - alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group.

[0149] Examples of the structural unit (a4) include a structural unit represented by formula (a4-0), a structural unit represented by formula (a4-1), and a structural unit represented by formula (a4-4). In formula (a4-0), TIFF2025090653000096.tif4247 R 54 represents a hydrogen atom or a methyl group. L 4a represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 3a represents a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms. In formula (a4-4), R 64 represents a hydrogen atom or a fluorine atom.

[0150] Examples of the alkanediyl group in L 4a include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. Examples of the perfluoroalkanediyl group in L include a difluoromethylene group, a perfluoroethylene group, a perfluoropropane-1,1-diyl group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, and a perfluoropentane-1, Examples of the perfluorocycloalkanediyl group in L include a perfluorocyclopropane-1,1-diyl group, a perfluorocyclopropane-1,2-diyl group, a perfluorocyclobutane-1,2-diyl group, a perfluorocyclopentane-1,2-diyl group, a perfluorocyclohexane-1,2-diyl group, a perfluorocycloheptane-1,2-diyl group, and a perfluorocyclooctane-1,2-diyl group.

[0151] Examples of the alkanediyl group in L 3a include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. Examples of the perfluoroalkanediyl group in L include a difluoromethylene group, a perfluoroethylene group, a perfluoropropane-1,1-diyl group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, and a perfluoropentane-1, Examples of the perfluorocycloalkanediyl group in L ,2-diyl group, a perfluorocyclopentane-1,2-diyl group, a perfluorocyclohexane-1,2-diyl group, a perfluorocycloheptane-1,2-diyl group, and a perfluorocyclooctane-1,2-diyl group. 5-Diyl group, perfluoropentane-2,2-diyl group, perfluoropentane-3, 3-Diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2, 2-Diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1, 7-Diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3, 4-Diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1, 8-Diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3, 3-Diyl group, perfluorooctane-4,4-diyl group and the like can be mentioned. L 3a As the perfluorocycloalkanediyl group in, perfluorocyclohe xanediyl group, perfluorocyclopentanediyl group, perfluorocycloheptane di yl group, perfluoroadamantanediyl group and the like can be mentioned.

[0152] L 4a is preferably a single bond, a methylene group or an ethylene group, more preferably a single bond, a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0153] As the structural unit (a4-0), the structural units shown below and the structural units in the following structural units ( a4-0) in which the methyl group corresponding to R 54 is replaced by a hydrogen atom can be mentioned. TIFF2025090653000097.tif94165

[0154] ​​TIFF2025090653000098.tif4966[In formula (a4-1), R a41 represents a hydrogen atom or a methyl group. R a42 represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. A a41 represents an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a group represented by formula (a-g 1). However, at least one of A a41 and R a42 has a halogen atom (preferably a fluorine atom) as a substituent. TIFF2025090653000099.tif1687[In formula (a-g1), s represents 0 or 1. A a42 and A a44 each independently represent a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. A a43 represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent . X a41 and X a42 each independently represent -O-, -CO-, -CO-O- or -O-CO -. However, the total number of carbon atoms of A a42 , A a43 , A a44 , X a41 and X a42 is 7 or less. ] * represents a bonding site, and the * on the right side is the bonding site with -O-CO-R a42 . ]

[0155] R a42 Examples of the saturated hydrocarbon group in R include a chain saturated hydrocarbon group and a monocyclic or polycyclic saturated Examples thereof include an alicyclic hydrocarbon group and a group formed by combining these groups and the like.

[0156] Examples of the chain saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a he xadecyl group, a heptadecyl group, an octadecyl group, and the like. Examples of the monocyclic or polycyclic saturated alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group , a cycloheptyl group, a cyclooctyl group; polycyclic alicyclic hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bonding site). and the like. TIFF2025090653000100.tif11158Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanedi yl groups with one or more saturated alicyclic hydrocarbon groups, and include -alkanediyl group-saturated alicyclic hydrocarbon group, -saturated alicyclic hydrocarbon group-alkyl group, -alkanediyl group-saturated alicyclic hydrocarbon group-alkyl group, and the like. and the like.

[0157] R a42 Examples of the substituent that R may have include at least one selected from the group consisting of a halogen atom and a group represented by the formula (a-g3). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and preferably a fluorine atom. . TIFF2025090653000101.tif856[In the formula (a-g3), X a43 represents an oxygen atom, a carbonyl group, **-O-CO- or **-CO-O-. A a45represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. * is R a42 represents the bonding site with.] However, in R a42 -X a43 -A a45 when R a42 does not have a halogen atom, A a4 5 represents a saturated hydrocarbon group having 1 to 17 carbon atoms having at least one halogen atom.

[0158] A a45 Examples of the saturated hydrocarbon group in include methyl group, ethyl group, propyl group, butyl group , pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentade cyl group, hexadecyl group, heptadecyl group, octadecyl group and other alkyl groups; cyclope ntyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and other monocyclic alicyclic hydrocarbon groups; and decahydronaphthyl group, adamantyl group, norbornyl group and the following group (* represents the bonding site.) and other polycyclic alicyclic hydrocarbon groups. Examples of the group formed by the combination of TIFF2025090653000102.tif10158 include groups formed by combining one or more alkyl groups or one or more alkanedi yl groups with one or more alicyclic hydrocarbon groups, and include -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, -al kanediyl group-alicyclic hydrocarbon group-alkyl group and the like.

[0159] R a42 is preferably a saturated hydrocarbon group which may have a halogen atom, and an alkyl group having a halogen atom and / or a saturated hydrocarbon group having a group represented by the formula (a-g3) are more preferred. ​​R a42 When R is a saturated hydrocarbon group having a halogen atom, it preferably has a fluorine atom and is a saturated hydrocarbon group, more preferably a perfluoroalkyl group or a perfluoro cycloalkyl group, still more preferably a perfluoroalkyl group having 1 to 6 carbon atoms and particularly preferably a perfluoroalkyl group having 1 to 3 carbon atoms. Examples of the perfluoroalkyl group include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group , a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group, a perfluoro heptyl group, a perfluorooctyl group, and the like. Examples of the perfluorocycloalkyl group include a perfluorocyclohexyl group and the like. R a42 When R is a saturated hydrocarbon group having a group represented by the formula (a-g3), including the number of carbon atoms contained in the group represented by the formula (a- g3), the total number of carbon atoms of R a42 is preferably 15 or less and more preferably 12 or less. When having a group represented by the formula (a-g3) as a substituent, the number thereof is preferably 1.

[0160] R a42 When R is a saturated hydrocarbon group having a group represented by the formula (a-g3), R a42 is more preferably a group represented by the formula (a-g2). In the formula (a-g2), TIFF2025090653000103.tif872 A a46 represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom . X a44 represents -O-CO- or -CO-O- (** represents the bonding site with A a46 ). ) A a47represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. However, A a46 , A a47 and X a44 have a total carbon number of 18 or less, and at least one of A a46 and A a47 has at least one halogen atom. * represents the bonding site with the carbonyl group.] * represents the bonding site with the carbonyl group.]

[0161] The saturated hydrocarbon group of A a46 preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms. The saturated hydrocarbon group of A a47 preferably has 4 to 15 carbon atoms, more preferably 5 to 12 carbon atoms, and A a 47 is more preferably a cyclohexyl group or an adamantyl group.

[0162] The preferred structure of the group represented by formula (a-g2) is the following structure (* is the bonding site with the carbonyl group ). TIFF2025090653000104.tif13160

[0163] As the alkanediyl group in A a41 , there may be mentioned linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1, 3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1 ,6-diyl group; and branched alkanediyl groups such as a propane-1,2-diyl group, a butane-1 ,3-diyl group, a 2-methylpropane-1,2-diyl group, a 1-methylbutane-1,4- diyl group, a 2-methylbutane-1,4-diyl group and the like. are mentioned. As the substituent in the alkanediyl group represented by A a41 , there may be mentioned a hydroxy group and an alkoxy group having 1 to 6 carbon atoms and the like. A a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably an alkanediyl group having 2 to 4 carbon atoms, and even more preferably an ethylene group.

[0164] Regarding A in the group represented by formula (a-g1) a42 , A a43 and A a44 The divalent saturated hydrocarbon groups represented include linear or branched alkanediyl groups and monocyclic divalent alicyclic saturated hydrocarbon groups , and groups formed by combining an alkanediyl group and a divalent alicyclic saturated hydrocarbon group etc. may be mentioned. Specifically, a methylene group, an ethylene group, propane-1,3-di yl group, propane-1,2-diyl group, butane-1,4-diyl group, 1-methylpropane -1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1 ,2-diyl group, etc. may be mentioned. A a42 , A a43 and A a44 The substituents of the divalent saturated hydrocarbon group represented include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms, etc. may be mentioned. s is preferably 0.

[0165] In the group represented by formula (a-g1), X a42 is -O-, -CO-, -CO-O- or -O-CO- The groups include the following groups, etc. In the following examples, * and ** each represent a bonding site, and ** is the bonding site with -O-CO-R a42 . TIFF2025090653000105.tif50151

[0166] Regarding the structural unit represented by formula (a4-1), the following structural units and the following structural units In the structural unit represented by the formula (a4-1), R a41 The methyl group corresponding to is replaced by a hydrogen atom, and examples of the structural unit include TIFF2025090653000106.tif98145

[0167] TIFF2025090653000107.tif123142

[0168] Examples of the structural unit represented by the formula (a4-1) include the structural unit represented by the formula (a4-2) and the structural unit represented by the formula (a4-3). TIFF2025090653000108.tif4156[In the formula (a4-2), R f5 represents a hydrogen atom or a methyl group. L 44 represents an alkanediyl group having 1 to 6 carbon atoms, and -C H2- contained in the alkanediyl group may be replaced by -O- or -CO-. R f6 represents a saturated hydrocarbon group having a fluorine atom and 1 to 20 carbon atoms. However, the upper limit of the total number of carbon atoms of 44 L and f6 R is 21.]

[0169] Examples of the alkanediyl group having 1 to 6 carbon atoms of 44 L are the same groups as those exemplified by a41 A. Examples of the saturated hydrocarbon group of f6 R are the same groups as those exemplified by 42 R. As the alkanediyl group in 44 L, an alkanediyl group having 2 to 4 carbon atoms is preferable , and an ethylene group is more preferable.

[0170] Examples of the structural unit represented by the formula (a4-2) include, for example, the formulas (a4-1-1) to (a4 ​Examples thereof include structural units represented by (a4-2). In the structural unit (a4-2), R f5 A structural unit in which the methyl group corresponding to is replaced by a hydrogen atom is also represented by the formula (a4-2) and is included as a structural unit.

[0171] TIFF2025090653000109.tif5672[In the formula (a4-3), R f7 represents a hydrogen atom or a methyl group. L 5 represents an alkanediyl group having 1 to 6 carbon atoms. A f13 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms which may have a fluorine atom. That's all. X f12 represents *-O-CO- or *-CO-O- (* represents the bonding site with A f13 ). ) A f14 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, at least one of A f13 and A f14 has a fluorine atom, and the total carbon number of L 5 , A f13 and A f14 has an upper limit of 20.]

[0172] L 5 Examples of the alkanediyl group in include the same groups as those exemplified for the alkanediyl group of A a41 . The same groups are included.

[0173] A f13 Examples of the divalent saturated hydrocarbon group which may have a fluorine atom in include preferably a divalent chain saturated hydrocarbon group which may have a fluorine atom and a divalent alicyclic saturated hydrocarbon group which may have a fluorine atom, more preferably a perfluoroalkanediyl group. group. It is an Ru group. Examples of the divalent chain saturated hydrocarbon group which may have a fluorine atom include alkane diyl groups such as a methylene group, an ethylene group, a propane diyl group, a butane diyl group and a pentane diyl group ; perfluoroalkane diyl groups such as a difluoromethylene group, a perfluoroethylene group, a perfluoropropane diyl group, a perfluorobutane diyl group and a perfluoropentane diyl group, etc. ; perfluoroalkane diyl groups such as a difluoromethylene group, a perfluoroethylene group, a perfluoropropane diyl group, a perfluorobutane diyl group and a perfluoropentane diyl group, etc. ; perfluoroalkane diyl groups such as a difluoromethylene group, a perfluoroethylene group, a perfluoropropane diyl group, a perfluorobutane diyl group and a perfluoropentane diyl group, etc. are exemplified. The divalent alicyclic saturated hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include a cyclohexane diyl group and a perfluorocyclohexane diyl group, etc. Examples of the polycyclic group include an adamantane diyl group, a norbornane diyl group, a perfluoroadamantane diyl group, etc. The divalent alicyclic saturated hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include a cyclohexane diyl group and a perfluorocyclohexane diyl group, etc. Examples of the polycyclic group include an adamantane diyl group, a norbornane diyl group, a perfluoroadamantane diyl group, etc. The divalent alicyclic saturated hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include a cyclohexane diyl group and a perfluorocyclohexane diyl group, etc. Examples of the polycyclic group include an adamantane diyl group, a norbornane diyl group, a perfluoroadamantane diyl group, etc. are exemplified.

[0174] A f14 saturated hydrocarbon group and a saturated hydrocarbon group which may have a fluorine atom are groups similar to those exemplified by R a42 . Among them, a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1 ,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3, ,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2, ,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2 ,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group , a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group and a per fluoro octyl group and other alkyl fluoride groups, a cyclopropylmethyl group, a cyclopropyl group , etc. are exemplified. , cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantylmethyl group, etc. are preferable. , norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantylmethyl group, etc. are preferable. ylmethyl group, etc. are preferable.

[0175] In formula (a4-3), L 5 is preferably an ethylene group. A f13 The divalent saturated hydrocarbon group of is preferably a group containing a divalent chain saturated hydrocarbon group having 1 to 6 carbon atoms and a divalent alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and a divalent chain saturated hydrocarbon group having 2 to 3 carbon atoms is more preferable. A f14 The saturated hydrocarbon group of is preferably a group containing a chain saturated hydrocarbon group having 3 to 12 carbon atoms and an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and a group containing a chain saturated hydrocarbon group having 3 to 10 carbon atoms and an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms is more preferable. Among them, A is preferably a group containing an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, more preferably a cyclopropylmethyl group, cyclopentyl group, cyclohexyl group, norbornyl group and adamantyl group. f14 is , preferably a group containing an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, more preferably a cyclopropylmethyl group, cyclopentyl group, cyclohexyl group, norbornyl group and adamantyl group.

[0176] Examples of the structural unit represented by formula (a4-3) include structural units represented by formula (a4-1’-1) to formula (a 4-1’-11), respectively. The structural unit in which the methyl group corresponding to R in the structural unit (a4-3) is replaced by a hydrogen atom is also included in the structural units represented by formula (a4-3). f7

[0177] ​​​​​​​Examples of the structural unit (a4) include the structural unit represented by the formula (a4-4). TIFF2025090653000110.tif4466[In the formula (a4-4), R f21 represents a hydrogen atom or a methyl group. A f21 represents -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -, or -(CH2) j4 -. CO-O-(CH2) j5 - is represented. j1 to j5 each independently represent an integer from 1 to 6. R f22 represents a saturated hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom.]

[0178] R f22 The saturated hydrocarbon group of a42 is the same as the saturated hydrocarbon group represented by R . R f22 represents an alkyl group having 1 to 10 carbon atoms and having a fluorine atom or an alicyclic saturated hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom, preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and still more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0179] In the formula (a4-4), A f21 is preferably -(CH2) j1 -, more preferably an ethylene group or a methylene group, and still more preferably a methylene group.

[0180] Examples of the structural unit represented by the formula (a4-4) include, for example, the following structural unit and the following formula In the structural unit represented, the methyl group corresponding to R f21 in the structural unit (a4-4) is replaced by a hydrogen atom.​​​ TIFF2025090653000111.tif86160

[0181] When the resin (A) has the structural unit (a4), its content is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, still more preferably 3 to 10 mol% based on all the structural units of the resin (A). mol% is more preferable with respect to all the structural units of the resin (A). % is even more preferable.

[0182] 〈Structural unit (a5)〉 Examples of the non-detachable hydrocarbon group possessed by the structural unit (a5) include groups having a linear, branched or cyclic hydrocarbon group. Among them, the structural unit (a5) preferably has an alicyclic hydrocarbon group. Among them, the structural unit (a5) preferably has a group having an alicyclic hydrocarbon group. group is preferred. Examples of the structural unit (a5) include, for example, a structural unit represented by the formula (a5-1). . TIFF2025090653000112.tif3555[In the formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with aliphatic hydrocarbon groups having 1 to 8 carbon atoms. hydrogen atoms may be substituted with aliphatic hydrocarbon groups having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.] -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0183] R 52 The alicyclic hydrocarbon group for R may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include, for example a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include, for example a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include, for example , an adamantyl group and a norbornyl group, etc. The aliphatic hydrocarbon group having 1 to 8 carbon atoms is, for example, a methyl group, an ethyl group, a propyl group, an iso propyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, and other alkyl groups. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group.

[0184] L 55 Examples of the divalent saturated hydrocarbon group in L include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and preferably a divalent chain saturated hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include alkane diyl groups such as a methylene group, an ethylene group, a propane diyl group, a butane diyl group, and a pentane diyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as a cyclopentane diyl group and a cyclohexane diyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include an adamantane diyl group and a norbornane diyl group.

[0185] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced with -O- or -CO- include groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom. In formula (L1-1),​​​ X x1 represents *-O-CO- or *-CO-O- (* represents the bonding site of L x1 .). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the total number of carbon atoms of L x1 and L x2 is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the total number of carbon atoms of L x3 and L x4 is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms of L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, the total number of carbon atoms of L x8 , L x9 and W x1 is 15 or less.

[0186] L x1is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably, a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0187] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF2025090653000114.tif54135

[0188] Examples of the group represented by formula (L1-2) include the following divalent groups. TIFF2025090653000115.tif23130

[0189] Examples of the group represented by formula (L1-3) include the following divalent groups. TIFF2025090653000116.tif16146

[0190] Examples of the group represented by formula (L1-4) include the following divalent groups. TIFF2025090653000117.tif26115

[0191] L 55 is preferably a single bond or a group represented by formula (L1-1).

[0192] Examples of the structural unit (a5-1) include the following structural units and the structural units in the following structural units ( a5-1) where the methyl group corresponding to R 51 is replaced by a hydrogen atom. are included. TIFF2025090653000118.tif77158

[0193] TIFF2025090653000119.tif38158 When the resin (A) has the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, still more preferably 3 to 15 mol% with respect to all the structural units of the resin (A). % is even more preferable.

[0194] <Structural unit (II)> The resin (A) may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (II)"). Specific examples of the structural unit (II) include the structural units described in JP-A-2016-79235, and those having a sulfonar in the side chain. A structural unit having a tosyl group or a carboxylate group and an organic cation, or a sulfonyl group in a side chain It is preferably a structural unit having an organic anion.

[0195] A structural unit having a sulfonate group or a carboxylate group and an organic cation in a side chain is preferably a structural unit represented by formula (II-2-A’). TIFF2025090653000120.tif3089[In formula (II-2-A’), X III3 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -S- or -CO-, and the hydrogen atom contained in the saturated hydrocarbon group may be replaced by a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, or a hydroxy group. A x1 represents an alkanediyl group having 1 to 8 carbon atoms, and the hydrogen atom contained in the alkanediyl group may be substituted by a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms . RA - represents a sulfonate group or a carboxylate group. R III3 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. ZA + represents an organic cation.]

[0196] R III3 Examples of the halogen atom represented by R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R III3 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by , R a8 ​​An alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by the same as that is exemplified. A x1 Examples of the alkanediyl group having 1 to 8 carbon atoms represented by include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group , a hexane-1,6-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-di yl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, a 2-methylbutane-1,4-diyl group and the like. . A x1 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms which may be substituted in include tri fluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroiso propyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-but yl group, a perfluoropentyl group, a perfluorohexyl group and the like. X III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by include a linear or branched a lkandiyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and combinations of these may be used. Specifically, a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1, 2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1 ,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane- 1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a do A linear alkanediyl group such as a decane-1,12-diyl group; a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, pen a branched alkanediyl group such as a tan-1,4-diyl group, a 2-methylbutane-1,4-diyl group, etc.; a divalent monocyclic alicyclic saturated hydrocarbon group such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclooctane-1,5-diyl group, etc.; a divalent polycyclic alicyclic saturated hydrocarbon group such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, etc. may be mentioned. Examples of those in which -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- include divalent groups represented by formula (X1) to formula (X53). However, the carbon number before -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- is 17 or less respectively. In the following formula, * and ** represent bonding sites, and * represents the bonding site with A

[0197]

[0198] * is A x1 represents the bonding site with. TIFF2025090653000121.tif145161

[0198] X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0199] ZA + The organic cation represented by is the same as the cation Z1 in salt (B1) + and examples thereof include those.

[0200] The structural unit represented by formula (II-2-A’) is preferably the structural unit represented by formula (II-2-A) is. TIFF2025090653000122.tif38110 [In formula (II-2-A), R III3 、X III3 and ZA + have the same meanings as described above. z represents any integer from 0 to 6. R III2 and R III4 each independently represent a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 6 carbon atoms. When z is 2 or more, a plurality of R and R III2 and R III4 may be the same as each other or different from each other. Q a and Q b each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. R III2 、R III4 、Q a and Q b Examples of the perfluoroalkyl group having 1 to 6 carbon atoms represented by include the same ones as the perfluoroalkyl group having 1 to 6 carbon atoms represented by the aforementioned Q b1 are those.

[0201] The structural unit represented by formula (II-2-A) is preferably the structural unit represented by formula (II-2-A-1) is. ​​TIFF2025090653000123.tif5677[In formula (II-2-A-1), R III2 、R III3 、R III4 、z, Q a 、Q b and ZA + have the same meanings as described above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, and the -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -S- or -CO-, and the hydrogen atoms contained in the saturated hydrocarbon group may be replaced by halogen atoms or hydroxy groups.] R III5 Examples of the saturated hydrocarbon group having 1 to 12 carbon atoms represented by include linear or branched alkyl groups such as methyl group, ethyl group, prop yl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pent yl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group and dodecyl group. X I2 Examples of the divalent saturated hydrocarbon group represented by III3 include those similar to the divalent saturated hydrocarbon group represented by X

[0202] As the structural unit represented by formula (II-2-A-1), the structural unit represented by formula (II-2-A-2) is more preferable. TIFF2025090653000124.tif5187[In formula (II-2-A-2), R III3 、R III5 and ZA + have the same meanings as described above. m and n each independently represent 1 or 2.]

[0203] ​Examples of the structural unit represented by the formula (II-2-A') include the following structural units, R III3 The group corresponding to the methyl group of is a hydrogen atom, a halogen atom (e.g., a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.) and the structural units described in International Publication No. WO2012 / 050015 . ZA . + represents an organic cation. TIFF2025090653000125.tif86163

[0204] The structural unit having a sulfonio group and an organic anion in the side chain is preferably a structural unit represented by the formula (II-1-1). TIFF2025090653000126.tif3482[In the formula (II-1-1), A II1 represents a single bond or a divalent linking group. R II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R II2 and R II3 each independently represent a hydrocarbon group having 1 to 18 carbon atoms, and R II2 and R II3 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. R II4 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A - represents an organic anion. ]] R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by II1 include a phenylene group and a naphthylene group, etc. R II2 and R II3 Examples of the hydrocarbon group represented by II2 and II3 include an alkyl group, an alicyclic hydrocarbon group, an aromatic Examples include hydrocarbon groups and groups formed by combining these groups. Examples of the alkyl group and the alicyclic hydrocarbon group are the same as those described above. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, and phenanthryl group. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group , aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphen yl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesity yl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic carbon hydrogen group (p-cyclohexylphenyl group, p-adamantyl phenyl group, etc.), aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. are included. R II4 Examples of the halogen atom represented by R include fluorine atom, chlorine atom, bromine atom and iodine atom, etc. R II4 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R are the same as those of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R a8 and are included. A II1 Examples of the divalent linking group represented by A include, for example, a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-. Specifically, examples are the same as those of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by X III3 and are included.

[0205] Examples of the structural unit containing the cation in formula (II-1-1) include the structural unit represented by the following and and R II4 a group corresponding to the methyl group of is a hydrogen atom, a fluorine atom, a trifluoromethyl group, etc. Examples of the structural unit in which is replaced include those. TIFF2025090653000127.tif85130

[0206] A - Examples of the organic anion represented by include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, carboxylic acid anions, and the like. A - The organic anion represented by is preferably a sulfonate anion. Examples of the sulfonate anion include the same ones as the anions contained in the salt represented by the aforementioned formula (I-A).

[0207] A - Examples of the sulfonylimide anion represented by include the following. TIFF2025090653000128.tif36136

[0208] Examples of the sulfonylmethide anion include the following. TIFF2025090653000129.tif29123

[0209] Examples of the carboxylic acid anion include the following. TIFF2025090653000130.tif51153

[0210] Examples of the structural unit represented by formula (II-1-1) include the structural unit represented by the following and the like. TIFF2025090653000131.tif98156

[0211] When the resin (A) contains the structural unit (II), the content of the structural unit (II) is​ With respect to all the structural units of resin (A), it is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and still more preferably 3 to 10 mol%.

[0212] Resin (A) may have structural units other than the above-mentioned structural units, and examples of such structural units include structural units well-known in the art.

[0213] Resin (A) is preferably a resin composed of structural unit (a1) and structural unit (s). . Structural unit (a1) is preferably at least one selected from the group consisting of structural unit (a1-0), structural unit (a1-1), and structural unit (a1-2) (preferably the structural unit having a cyclohexyl group and a cyclopentyl group), and structural unit (a1-4), more preferably at least two kinds, and still more preferably at least two kinds selected from the group consisting of structural unit (a1-1) and structural unit (a1-2). Structural unit (s) is preferably at least one selected from the group consisting of structural unit (a2) and structural unit (a3). Structural unit (a2) is preferably structural unit (a2-1) or structural unit (a2-A). Structural unit (a3) is preferably at least one selected from the group consisting of the structural unit represented by formula (a3-1), the structural unit represented by formula (a3-2), and the structural unit represented by formula (a3-4).

[0214] Each structural unit constituting resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers leading to these structural units. The content of each structural unit contained in resin (A) is based on the monomers used in the polymerization ​​​It can be adjusted by the amount of monomer used. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,5 00 or more, still more preferably 3,000 or more), and 50,000 or less (more preferably 30 ,000 or less, still more preferably 15,000 or less). In this specification, the weight average molecular weight is the value determined by the conditions described in the examples by gel permeation chromatography .

[0215] <Resin other than resin (A)> The resist composition of the present invention may further contain a resin other than the resin (A). Examples of the resin other than the resin (A) include resins containing the structural unit (a4) or the structural unit (a5) (hereinafter sometimes referred to as resin (X)).

[0216] Among them, as the resin (X), a resin containing the structural unit (a4) is preferable. That is, it is preferably a resin containing a structural unit having a fluorine atom. In the resin (X), the content of the structural unit (a4) is preferably 30 mol% or more, more preferably 40 mol% or more with respect to the total of all the structural units of the resin (X), and still more preferably 45 mol% or more. Examples of the structural unit that the resin (X) may further have include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. Among them, the resin ( X) is preferably a resin composed of only the structural unit (a4) and / or the structural unit (a5), more preferably a resin composed of only the structural unit (a4).

[0217] Each structural unit constituting the resin (X) may be used alone or in combination of two or more, Using the monomers that induce these structural units, it can be produced by a known polymerization method (for example, radical polymerization method). The content of each structural unit in the resin (X) can be adjusted by the amount of monomers used in the polymerization. The weight average molecular weight of the resin (X) is preferably 6,000 or more (more preferably 7,000 or more), and 80,000 or less (more preferably 60,000 or less). The means for measuring the weight average molecular weight of the resin (X) is the same as that of the resin (A). When the resist composition contains the resin (X), its content is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, even more preferably 1 to 40 parts by mass, particularly preferably 2 to 30 parts by mass, and particularly preferably 2 to 8 parts by mass, based on 100 parts by mass of the resin (A). The content of the resin (A) in the resist composition is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. When the resist composition contains a resin other than the resin (A), the total content of the resin (A) and the resin other than the resin (A) is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. The solid content of the resist composition and the content of the resin relative thereto can be measured by known analytical means such as liquid chromatography or gas chromatography. <Solvent (E)> The content of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less, preferably 92% by mass or more and 99% by mass or less, more preferably 94% by mass or more and 98% by mass or less.

[0218]

[0219] ​​​​​​​​​​It is 99% by mass or less. The content of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography. Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; and the like. One kind of the solvent (E) may be used alone, or two or more kinds may be used.

[0220] <Quencher (C)> Examples of the quencher (C) include basic nitrogen-containing organic compounds and salts that generate an acid having a lower acidity than the acid generated from the acid generator (B). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15% by mass, more preferably about 0.01 to 10% by mass, even more preferably about 0.01 to 7% by mass, and even more preferably about 0.1 to 3% by mass, based on the solid content of the resist composition. Examples of the basic nitrogen-containing organic compounds include amines and ammonium salts. Examples of the amines include aliphatic amines and aromatic amines. Examples of the aliphatic amines include primary amines, secondary amines, and tertiary amines. Examples of the amines include 1-naphthylamine, 2-naphthylamine, aniline, diisopropyl Ruaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylani line, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine , octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylam ine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine , methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibut ylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine , ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohe xylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triiso propanolamine, ethylenediamine, tetramethylenediamine, hexamethylenedia mine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3' -dimethyl diphenylmethane, 4,4'-diamino-3,3'-diethyl diphenylmeth ane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridi ne, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 1,2-di(4-pyridi yl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di( (2-pyridyl)ketone, 4,4'-dipyridyl sulfide, 4,4'-dipyridyl disulfide 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine, etc. are exemplified, preferably aromatic amines such as diisopropyl aniline are exemplified, and more preferably 2,6-diisopropyl aniline is exemplified. Examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropyl ammonium hydroxide, tetrabutylammonium hydroxide, tetrahexyl ammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethyl ammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, choline, etc. are exemplified.

[0221] The acidity of the salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is indicated by the acid dissociation constant (pKa). The salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is a salt in which the acid dissociation constant of the acid generated from the salt is usually -3 < pKa, preferably a salt of -1 < pKa < 7, and more preferably a salt of 0 < pKa < 5. Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-3 9502, and JP-A-2011-191745. Preferably is a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (B), and more preferably, is an intramolecular salt (D) of a weak acid. (A salt having a carboxylate anion), and more preferably, is an intramolecular salt (D) of a weak acid. TIFF2025090653000132.tif84165

[0222] Examples of the intramolecular salt (D) of a weak acid include the following salts. TIFF2025090653000133.tif72165

[0223] <Other Components> The resist composition of the present invention may contain, if necessary, components other than the above-described components (hereinafter sometimes referred to as "other components (F)"). There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used. There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used. There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used. There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used.

[0224] <Preparation of Resist Composition> The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. The resist composition of the present invention can be prepared by mixing the salt (I), the resin (A), and, if necessary, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is not particularly limited, and stirring and mixing, etc. can be used. After mixing the respective components, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm. After mixing the respective components, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

[0225] <Method for Manufacturing Resist Pattern> The method for manufacturing a resist pattern of the present invention comprises (1) a step of applying the resist composition of the present invention onto a substrate; (2) a step of drying the applied composition to form a composition layer; (3) a step of exposing the composition layer; (4) a step of heating the exposed composition layer; and (5) a step of developing the heated composition layer. To apply the resist composition onto the substrate, it can usually be carried out by using a commonly used apparatus such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers. Before applying the resist composition, the substrate may be cleaned, and an antireflection film or the like may be formed on the substrate. By After drying the applied composition, the solvent is removed to form a composition layer. Drying can be carried out, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-bake), or by using a decompression device. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during decompression drying is preferably about 1 to 1.0×10 Pa. The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, various light sources can be used, such as those that emit ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), those that wavelength-convert laser light from a solid laser light source (such as YAG or semiconductor laser) to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams, and those that irradiate extreme ultraviolet light (EUV). Note that in this specification For example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-bake), or by using a decompression device. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during decompression drying is preferably about 1 to 1.0×10 Pa. is preferably the case, and the heating time is preferably 10 to 180 seconds. Also, the pressure during vacuum drying is carried out is preferably about 1 to 1.0×10 5 Pa. The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), laser light from a solid laser light source (such as YAG or semiconductor laser) wavelength-converted to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, electron beams, extreme ultraviolet light (EUV), etc. can be used. Note that in this specification may be. As the exposure light source, ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), laser light from a solid laser light source (such as YAG or semiconductor laser) wavelength-converted to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, electron beams, extreme ultraviolet light (EUV), etc. can be used. Note that in this specification laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm) and other ultraviolet region laser light emitting laser, laser light from a solid laser light source (YAG or semiconductor laser, etc.) wavelength-converted to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, electron beams, and ultraviolet light (EUV) irradiating ones, etc., various ones can be used. In addition, in this specification ultraviolet light (EUV) irradiating ones, etc., various ones can be used. In addition, in this specification In some cases, the irradiation of these radiations is collectively referred to as "exposure". During exposure , usually, exposure is performed through a mask corresponding to the required pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask. The composition layer after exposure is heat-treated (so-called post-exposure bake) to promote the deprotection reaction at the acid-labile group. The heating temperature is usually about 50 to 200 °C, preferably about 70 to 150 °C. The composition layer after heating is usually developed using a developer with a developing apparatus. Examples of the developing method include dip method, paddle method, spray method, dynamic dispense method, etc. The developing temperature is preferably, for example, 5 to 60 °C, and the developing time is preferably, for example, 5 to 300 seconds. By selecting the type of developer as follows , a positive resist pattern or a negative resist pattern can be manufactured. When manufacturing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. For example, aqueous solutions of tetramethylammonium hydroxide and (2-hydroxy ethyl)trimethylammonium hydroxide (commonly called choline) can be mentioned. The alkaline developer may contain a surfactant. After development, it is preferable to wash the resist pattern with ultrapure water and then remove the water remaining on the substrate and the pattern. When manufacturing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic-based developer") is used as the developer. Examples of the organic solvent contained in the organic developing solution include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether acetate solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole, etc. In the organic developing solution, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and still more preferably consisting essentially of only the organic solvent. Among them, as the organic developing solution, a developing solution containing butyl acetate and / or 2-heptanone is preferred. In the organic developing solution, the total content of butyl acetate and 2-heptanone is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and still more preferably consisting essentially of only butyl acetate and / or 2-heptanone. The organic developing solution may contain a surfactant. Also, the organic developing solution may contain a trace amount of water. During development, development may be stopped by substituting with a solvent of a different type from the organic developing solution. After development, it is preferable to wash the resist pattern with a rinse solution. The rinse solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After washing, it is preferable to remove the rinse solution remaining on the substrate and the pattern. 〈Use〉

[0226] ​​​​​​​​​The resist composition of the present invention is a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, and is particularly suitable as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for fine processing of semiconductors. A resist composition for excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, and is particularly suitable as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for fine processing of semiconductors. V exposure, particularly suitable as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and useful for semiconductor microfabrication. It is suitable as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for fine processing of semiconductors.

Examples

[0227] The present invention will be further specifically described with reference to examples. In the examples, “%” and “parts” representing the content or usage amount are based on mass unless otherwise specified. “%” and “parts” representing the content or usage amount are based on mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography. The analysis conditions for gel permeation chromatography are as follows. Column: TSKgel Multipore HXL-M x 3 + guard column (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 °C Injection volume: 100 μl Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC is Agilent 1100 type, MASS is Agilent ent LC / MSD type). In the following examples, the value of this molecular ion peak is indicated by “MASS”. In the following examples, the value of this molecular ion peak is indicated by “MASS”.

[0228] Example 1: Synthesis of the salt represented by formula (I-1) 3.00 parts of the salt represented by formula (I-1-a), 15 parts of dimethylformamide, and 2.31 parts of potassium carbonate were mixed, stirred at 23 °C for 30 minutes, and then heated to 75 °C. The resulting mixture was stirred at 23 °C for 30 minutes and then heated to 75 °C. The resulting To the mixture, 5.08 parts of the compound represented by the formula (I-1-b) and 0.69 part of potassium iodide were added, and after stirring at 75 °C for 2 hours, the mixture was cooled to 23 °C. To the resulting mixture, 30 parts of chloroform and 15 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the obtained organic layer, 15 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. After concentrating the obtained organic layer, to the concentrated residue, 1.5 parts of acetonitrile and 30 parts of tert-butyl methyl ether were added, and after stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 6.45 parts of the salt represented by the formula (I-1-c). TIFF2025090653000135.tif52170 6.45 parts of the salt represented by the formula (I-1-c), 20 parts of chloroform and 1.78 parts of the salt represented by the formula (I-1-d) were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 10 parts of a 5% aqueous oxalic acid solution were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the obtained organic layer, 10 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. After concentrating the obtained organic layer, to the concentrated residue, 1 part of acetonitrile and 30 parts of tert-butyl methyl ether were added, and after stirring at 23 °C for 30 minutes, the mixture was filtered to obtain 2.85 parts of the salt represented by the formula (I-1). MASS(ESI(+)Spectrum):M + 1391.7 MASS(ESI(-)Spectrum):M - 323.0

[0229] Example 2: Synthesis of the salt represented by the formula (I-29) 3.00 parts of the salt represented by TIFF2025090653000136 formula (I-1-a), 20 parts of chloroform and formula (I-1-d) 1.78 parts of the salt represented by were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 10 parts of a 5% aqueous solution of oxalic acid was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the obtained organic layer, 10 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and then to the concentrated residue, 1 part of acetonitrile and 30 parts of tert-butyl methyl ether were added. After stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 1.88 parts of the salt represented by formula (I-2 9). MASS(ESI(+)Spectrum): M 567.2 + MASS(ESI(-)Spectrum): M - 323.0

[0230] Example 3: Synthesis of the salt represented by formula (I-43) 3.00 parts of the salt represented by TIFF2025090653000137 formula (I-1-a), 15 parts of dimethylformamide and pyridine 1.46 parts were mixed and stirred at 23 °C for 30 minutes, and then the temperature was raised to 75 °C. To the resulting mixture, the compound represented by formula (I-43-b) was added, and after stirring at 75 °C for 2 hours, it was cooled to 2 3 °C. To the obtained mixture, 30 parts of chloroform and 15 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the obtained organic layer, 15 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and then to the concentrated residue, acetone 15 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. After concentrating the obtained organic layer, to the concentrated residue,​ Add 1.5 parts of nitrile and 30 parts of tert-butyl methyl ether, and stir at 23 °C for 30 minutes After stirring for 30 minutes, remove the supernatant and concentrate to obtain 4.67 parts of the salt represented by the formula (I-43-c). 4.67 parts of the salt obtained 4.67 parts of the salt represented by the formula (I-43-c), 20 parts of chloroform and 1.78 parts of the salt represented by the formula (I-1-d ) were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 10 parts of a 5% aqueous oxalic acid solution was added, and after stirring at 23 °C for 30 minutes, liquid separation was carried out to take out the organic layer 10 parts of ion-exchanged water was added to the obtained organic layer, and after stirring at 23 °C for 30 minutes, liquid separation was carried out to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated After that, 1 part of acetonitrile and 30 parts of tert-butyl methyl ether were added to the concentrated residue, and after stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 1.44 parts of the salt represented by the formula (I- 43). MASS(ESI(+)Spectrum):M + 967.4 MASS(ESI(-)Spectrum):M - 323.0

[0231] Example 4: Synthesis of the salt represented by the formula (I-17) 6.45 parts of the salt represented by the formula (I-1-c), 20 parts of chloroform and 3.84 parts of the salt represented by the formula (I-17-d ) were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 10 parts of a 5% aqueous oxalic acid solution was added, and after stirring at 23 °C for 30 minutes, liquid separation was carried out to take out the organic layer 10 parts of ion-exchanged water was added to the obtained organic layer, and after stirring at 23 °C for 30 minutes, The organic layer was separated and taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated After that, to the concentrated residue, 1 part of acetonitrile and 30 parts of tert-butyl methyl ether were added and the mixture was stirred at 23 °C for 30 minutes and then filtered to obtain 4.12 parts of the salt represented by the formula (I-17). MASS(ESI(+)Spectrum): M + 1391.7 MASS(ESI(-)Spectrum): M - 793.3

[0232] Example 5: Synthesis of the salt represented by the formula (I-13) 6.45 parts of the salt represented by the formula (I-1-c), 20 parts of chloroform and 2.20 parts of the salt represented by the formula (I-13-d ) were mixed and stirred at 23 °C for 2 hours. To the obtained mixture, 10 parts of a 5% aqueous oxalic acid solution was added and the mixture was stirred at 23 °C for 30 minutes and then separated to take out the organic layer. To the obtained organic layer, 10 parts of ion-exchanged water was added and the mixture was stirred at 23 °C for 30 minutes and then separated to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated After that, to the concentrated residue, 1 part of acetonitrile and 30 parts of tert-butyl methyl ether were added and the mixture was stirred at 23 °C for 30 minutes and then filtered to obtain 3.61 parts of the salt represented by the formula (I-13). MASS(ESI(+)Spectrum): M + 1391.7 MASS(ESI(-)Spectrum): M - 423.1

[0233] Synthesis of resin The compounds (monomers) used for the synthesis of resin (A) are shown below. Hereinafter, these compounds ​​According to the formula number, it is referred to as "monomer (a1-1-3)" and the like. TIFF2025090653000141.tif3897

[0234] Synthesis Example 1 [Synthesis of Resin A1] As monomers, monomer (a1-4-2), monomer (a1-1-3) and monomer (a1-2-6) were used and mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-1 -3): monomer (a1-2-6)] was 38:24:38, and furthermore, 1.5 times the mass of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, azobisisobutyronitrile was added so as to be 7 mol% respectively based on the total number of moles of all monomers, and this was polymerized by heating at 85 °C for about 5 hours. Then, an aqueous solution of p-toluenesulfonic acid was added to the polymerization reaction solution, stirred for 6 hours, and then separated. The obtained organic layer was poured into a large amount of n -heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A1 (copolymer) having a weight average molecular weight of about 5. 3×10 at a yield of 78%. This resin A1 has the following structure 3 units. It has structural units. TIFF2025090653000142.tif29127

[0235] Synthesis Example 2 [Synthesis of Resin A2] As monomers, monomer (a1-4-2) and monomer (a1-2-6) were used, and the molar ratio [monomer (a1-4-2): monomer (a1-2-6)] was 38:62 and mixed. Furthermore, 1.5 times the mass of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, as an initiator was added. Azobisisobutyronitrile was added in an amount of 7 mol% respectively based on the total number of moles of all monomers and the mixture was polymerized by heating at 85 °C for about 5 hours. Then, an aqueous solution of p-toluenesulfonic acid was added to the polymerization reaction solution, and the mixture was stirred for 6 hours and then separated by liquid separation. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A2 (copolymer) having a weight average molecular weight of about 5.7×10 in a yield of 86%. This resin A2 has the following structural units. TIFF2025090653000143.tif2692 3 TIFF2025090653000143.tif2692

[0236] <Preparation of Resist Composition> As shown in Table 1, the following components were mixed, and the resulting mixture was filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a resist composition.

Table 1

[0237] <Resin> A1, A2, Resin A1, Resin A2 <Salt (I)> I-1: Salt represented by formula (I-1) I-13: Salt represented by formula (I-13) I-17: Salt represented by formula (I-17) I-29: Salt represented by formula (I-29) I-43: Salt represented by formula (I-43) <Acid Generator> I-1-a: Salt represented by formula (I-1-a) TIFF2025090653000145.tif4962I-1-c: Salt represented by formula (I-1-c) TIFF2025090653000146.tif7287I-43-c: Salt represented by formula (I-43-c) ​​​​TIFF2025090653000147.tif6274<Quencher (C)> C1: Synthesized by the method described in JP-A-2011-39502 TIFF2025090653000148.tif4355<Solvent> 300 parts of propylene glycol monomethyl ether acetate 300 parts of propylene glycol monomethyl ether

[0238] (Electron beam exposure evaluation of resist composition) A 6-inch silicon wafer was treated on a direct hot plate with hexamethyldisilazane at 90 °C for 60 seconds. The resist composition was spin-coated onto this silicon wafer such that the film thickness of the composition layer was 0.04 μm. Thereafter, it was pre-baked on a direct hot plate at the temperature shown in the "PB" column of Table 1 for 60 seconds to form a composition layer. On the composition layer formed on the wafer, a line-and-space pattern (pitch 60 nm / line width 30 nm) was directly drawn using an electron beam lithography machine ["ELS-F1 25 125 keV" manufactured by Elionix, Inc.] while changing the exposure dose stepwise. After exposure, post-exposure bake was performed on a hot plate at the temperature shown in the "PEB" column of Table 1 for 60 seconds, and further paddle development was carried out with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide for 60 seconds to obtain a resist pattern. The obtained resist pattern (line-and-space pattern) was observed with a scanning electron microscope, and the exposure dose at which the line width and space width of the line-and-space pattern with a pitch of 60 nm were 1:1 was defined as the effective sensitivity. Line edge roughness evaluation (LER): The side walls of the resist pattern manufactured at the effective sensitivity The unevenness amplitude of the surface was measured with a scanning electron microscope to determine the line edge roughness. The results are shown in Table 2. The results are shown in Table 2.

Table 2

Industrial Applicability

[0239] The salt of the present invention and the resist composition containing the same are suitable for fine processing of semiconductors because a resist pattern having good line edge roughness (LER) can be obtained, and are extremely useful industrially. The salt of the present invention and the resist composition containing the same are suitable for fine processing of semiconductors because a resist pattern having good line edge roughness (LER) can be obtained, and are extremely useful industrially. The salt of the present invention and the resist composition containing the same are suitable for fine processing of semiconductors because a resist pattern having good line edge roughness (LER) can be obtained, and are extremely useful industrially.

Claims

1. A resist composition which contains a salt represented by formula (I) and does not contain a resin. [In formula (I), R １ and R ２ each independently represents a group having a hydroxy group or an acid labile group represented by formula (1). R ３ and R ４ each independently represents a hydrogen atom or a group represented by formula (IA). ３ and R ４ At least one of the groups is a group represented by formula (IA). [In formula (IA), R ５ and R ６ each independently represents a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, or a hydrocarbon group having 1 to 28 carbon atoms, and —CH 2 - may be replaced by -O-, -S- or -CO-, or R ５ and R ６ may be taken together with the carbon atom to which they are attached to form a single bond or an alkanediyl bridge having 1 to 6 carbon atoms, and the —CH ２ - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced with -. m5 represents an integer of 0 to 5, and when m5 is 2 or more, a plurality of R ５ may be the same or different from each other. m6 represents an integer of 0 to 5, and when m6 is 2 or more, a plurality of R ６ may be the same or different from each other. Q １ and Q. ２ each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. L １ represents a saturated hydrocarbon group having 1 to 24 carbon atoms, and the —CH ２ - may be replaced by -O- or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted by a fluorine atom or a hydroxy group. Y １ represents an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -SO ２ It may be replaced by --or --CO--. * indicates a binding site.] [In formula (1), R ａ１ , R ａ２ and R ａ３ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * indicates a binding site.]

2. R ５ and R ６ 2. The resist composition according to claim 1, wherein each of the groups independently represents a hydroxy group or a group having an acid labile group represented by formula (1).

3. R １ , R ２ , R ５ and R ６ 3. The resist composition according to claim 1, wherein the group having an acid labile group is a group represented by formula (IB-1). [In formula (IB-1), L ２ represents an alkanediyl group having 1 to 6 carbon atoms. R ａ１ , R ａ２ and R ａ３ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof; R a1 and R a2 are bonded to each other to form, together with the carbon atoms to which they are attached, a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms. * indicates a binding site.]

4. 4. The resist composition according to claim 1, further comprising a salt capable of generating an acid having a weaker acidity than the acid generated from the acid generator.

5. (1) a step of applying the resist composition according to any one of claims 1 to 4 onto a substrate; (2) A step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising the steps of:

Images